Compositions and methods for inducing conformational changes in cereblon and other e3 ubiquitin ligases

ABSTRACT

Provided herein are compositions, therapeutic methods, screening methods, computational methods and biomarkers based upon the elucidation of the interaction among cereblon, its substrates and certain compounds or agents, including small molecules, peptides, and proteins.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 14/752,588, filed Jun. 26, 2015, now U.S. Pat. No. 10,092,555, whichclaims priority to the U.S. provisional application No. 62/018,445,filed on Jun. 27, 2014, each of which is incorporated herein byreference in its entirety.

1. FIELD

Provided herein are compositions, therapeutic methods, screeningmethods, computational methods and biomarkers based upon the elucidationof the interaction among cereblon, its substrates and certain compoundsor agents, including small molecules, peptides, and proteins.

The content of the following submission on ASCII text file isincorporated herein by reference in its entirety: a computer readableform (CRF) of the Sequence Listing (File name:14247-327-999_SEQ_LISTING.txt, of size 32,632 bytes, created on Oct. 5,2018).

2. BACKGROUND 2.1 Cereblon

At least two isoforms of the protein cereblon (CRBN) exist, which are442 and 441 amino acids long, respectively, and CRBN is conserved fromplant to human. In humans, the CRBN gene has been identified as acandidate gene of an autosomal recessive nonsyndromic mental retardation(ARNSMR). See Higgins, J. J. et al., Neurology, 2004, 63:1927-1931. CRBNwas initially characterized as an RGS-containing novel protein thatinteracted with a calcium-activated potassium channel protein (SLO1) inthe rat brain, and was later shown to interact with a voltage-gatedchloride channel (CIC-2) in the retina with AMPK1 and DDB1. See Jo, S.et al., J. Neurochem, 2005, 94:1212-1224; Hohberger B. et al., FEBSLett, 2009, 583:633-637; Angers S. et al., Nature, 2006, 443:590-593.DDB1 was originally identified as a nucleotide excision repair proteinthat associates with damaged DNA binding protein 2 (DDB2). Its defectiveactivity causes the repair defect in the patients with xerodermapigmentosum complementation group E (XPE). DDB1 also appears to functionas a component of numerous distinct DCX (DDB1-CUL4-X-box) E3ubiquitin-protein ligase complexes which mediate the ubiquitination andsubsequent proteasomal degradation of target proteins. CRBN has alsobeen identified as a target for the development of therapeutic agentsfor diseases of the cerebral cortex. See WO 2010/137547 A1.

CRBN has recently been identified as a key molecular target that bindsto thalidomide to cause birth defects. See Ito, T. et al., Science,2010, 327:1345-1350. DDB1 was found to interact with CRBN and, thus, wasindirectly associated with thalidomide. Moreover, thalidomide was ableto inhibit auto-ubiquitination of CRBN in vitro, suggesting thatthalidomide is an E3 ubiquitin-ligase inhibitor. Id. Importantly, thisactivity was inhibited by thalidomide in wild-type cells, but not incells with mutated CRBN binding sites that prevent thalidomide binding.Id. The thalidomide binding site was mapped to a highly conservedC-terminal 104 amino acid region in CRBN. Id. Individual point mutantsin CRBN, Y384A and W386A were both defective for thalidomide binding,with the double point mutant having the lowest thalidomide-bindingactivity. Id. A link between CRBN and the teratogenic effect ofthalidomide was confirmed in animal models of zebra-fish and chickembryos. Id.

Whether binding to CRBN, the CRBN E3 ubiquitin-ligase complex, or one ormore substrates of CRBN, is required for the beneficial effects ofthalidomide and other drugs is yet to be established. Understandingthese interactions with thalidomide and other drug targets will allowthe definition of the molecular mechanisms of efficacy and/or toxicityand may lead to drugs with improved efficacy and toxicity profiles.

2.2 Compounds

A number of studies have been conducted with the aim of providingcompounds that can safely and effectively be used to treat diseasesassociated with abnormal production of TNF-α. See, e.g., Marriott, J.B., et al., Expert Opin. Biol. Ther., 2001, 1(4): 1-8; G. W. Muller, etal., J Med Chem., 1996, 39(17): 3238-3240; and G. W. Muller, et al.,Bioorg & Med Chem Lett., 1998, 8: 2669-2674. Some studies have focusedon a group of compounds selected for their capacity to potently inhibitTNF-α production by LPS stimulated PBMC. L. G. Corral, et al., Ann.Rheum. Dis., 1999, 58:(Suppl I) 1107-1113. These compounds show not onlypotent inhibition of TNF-α but also marked inhibition of LPS inducedmonocyte IL1β and IL12 production. LPS induced IL6 is also inhibited bysuch compounds, albeit partially. These compounds are potent stimulatorsof LPS-induced IL-10. Id.

Compounds for the methods provided herein include, but are not limitedto, the substituted 2-(2,6-dioxopiperidin-3-yl) phthalimides andsubstituted 2-(2,6-dioxopiperidin-3-yl)-1-oxoisoindoles described inU.S. Pat. Nos. 6,281,230 and 6,316,471, both to G. W. Muller, et al.Still other specific compounds disclosed herein belong to a class ofisoindole-imides disclosed in U.S. Pat. Nos. 6,395,754, 6,555,554,7,091,353, U.S. Publication No. 2004/0029832, and InternationalPublication No. WO 98/54170, each of which is incorporated herein byreference.

Thalidomide, lenalidomide and pomalidomide have shown remarkableresponses in patients with multiple myeloma, lymphoma and otherhematological diseases such as myelodysplastic syndrome. See GalustianC, et al., Expert Opin Pharmacother., 2009, 10:125-133. These drugsdisplay a broad spectrum of activity, including anti-angiogenicproperties, modulation of pro-inflammatory cytokines, co-stimulation ofT cells, increased NK cell toxicity, direct anti-tumor effects andmodulation of stem cell differentiation.

For example, thalidomide and lenalidomide have emerged as importantoptions for the treatment of multiple myeloma in newly diagnosedpatients, in patients with advanced disease who have failed chemotherapyor transplantation, and in patients with relapsed or refractory multiplemyeloma. Lenalidomide in combination with dexamethasone has beenapproved for the treatment of patients with multiple myeloma who havereceived at least one prior therapy. Pomalidomide may also beadministered in combination with dexamethasone. U.S. Patent PublicationNo. 2004/0029832 A1, the disclosure of which is hereby incorporated inits entirety, discloses the treatment of multiple myeloma.

Another compound provided herein is3-(5-amino-2-methyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione(“Compound A”), which has the following structure:

or an enantiomer or a mixture of enantiomers thereof; or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof.

Compound A can be prepared as described in U.S. Pat. No. 7,635,700, thedisclosure of which is incorporated herein by reference in its entirety.The compound can be also synthesized according to other methods apparentto those of skill in the art based upon the teaching herein. In certainembodiments, Compound A is in a crystalline form described in U.S.Provisional Pat. App. No. 61/451,806, filed Mar. 11, 2011, which isincorporated herein by reference in its entirety. In some embodiments,the hydrochloride salt of Compound A is used in the methods providedherein. Methods of treating, preventing and/or managing cancers andother diseases using Compound A are described in U.S. Provisional Pat.App. No. 61/451,995, filed Mar. 11, 2011, which is incorporated hereinby reference in its entirety.

Other compounds are provided in Section 5.8 herein.

Understanding the interactions of CRBN, the CRBN E3 ubiquitin-ligasecomplex, or one or more substrates of CRBN with thalidomide,lenalidomide, pomalidomide and other drug targets will allow thedefinition of the molecular mechanisms of efficacy and/or toxicity andmay lead to drugs with improved efficacy and toxicity profiles.

3. SUMMARY

We have discovered that CRBN has pluripotent potential as a drug targetfor the treatment of various diseases. We believe we are the first toreport and understand that cereblon can be induced to undergoconformational changes by use of certain small molecules or other agentsthat we will call “cereblon modifying agents” (CMAs). The use of theappropriate agent leads to a distinct conformational change or otheralteration in the properties of the CRBN surface, and a resultingdistinct phenotypic response. Cereblon is not simply a unidimensional ormonotypic protein that interacts with a single substrate. Instead,without being limited by theory, the conformational change or phenotypicresponse of cereblon or its pathway is dependent upon cell type and,most importantly, the CMA used to interact with cereblon or its pathway.

As such, we describe herein a variety of distinct conformationalchanges, surface property alterations, phenotypic responses and CMAs. Wealso describe treatment methods, compositions, drug screens andcomputational methods that exploit these discoveries.

We also describe the use of known agents as CMAs for new treatmentmethods. In another embodiment we disclose the use of new CMA or CMAclasses based upon the conformational change, alteration in surfaceproperties, or phenotypic response. It should be noted that thesediscoveries permit a plethora of methods to be used to treat diseasesassociated with cereblon pathway. Thus, also described herein are knownor new agents as CMAs for use in methods for treating diseases.

In one aspect, provided herein is a method of identifying a testcompound that induces a CRBN conformational change (e.g., within theCMA-binding pocket of the CRBN) or otherwise altering the properties ofa CRBN surface. In certain embodiments, the method comprises (a) (i)obtaining a first crystal structure of CRBN and a reference compound,and (ii) determining a three-dimensional structure of the first crystalby x-ray diffraction to obtain a first set of atomic coordinates; (b)(i) obtaining a second crystal comprising CRBN and the test compound,and (ii) determining a three-dimensional structure of the second crystalby x-ray diffraction to obtain a second set of atomic coordinates; and(c) comparing said first set of atomic coordinates with said second setof atomic coordinates; wherein a difference in atomic coordinates isindicative of a compound that induces a CRBN conformational change orotherwise alters the properties of a CRBN surface. In some embodiments,the first set of atomic coordinates and/or said second set of atomiccoordinates define a CMA binding domain. In certain embodiments, thedifference in atomic coordinates is determined by assessing differencesin atomic distances. Also provided herein is a test compound identifiedby this method. In some embodiments, the test compound induces a CRBNconformational change. In other embodiments, the test compound altersthe properties of the CRBN surface. In certain embodiments, theproperties of the CRBN surface are altered by the placement of compoundappendages. In certain embodiments, the conformational change oralteration occurs in a CMA binding pocket of the CRBN. In someembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on W380, W386 and/or W400 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on E377 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on V388 of CRBN. In certain embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on anadjacent region of the protein.

In certain embodiments of the various compositions and methods providedherein, the properties of the CRBN surface are altered by the placementof compound appendages.

In a second aspect, provided herein is a method of identifying a testcompound that induces a CRBN conformational change (e.g., within theCMA-binding pocket of the CRBN) or otherwise altering the properties ofa CRBN surface. In certain embodiments, the method comprises (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change orotherwise alters the properties of a CRBN surface. In some embodiments,the first three-dimensional structure is of a CRBN that is not bound toa reference compound (also sometimes referred to as an “unbound CRBN”herein, and which is not meant to preclude the CRBN being bound to otherproteins, e.g., DDB1). In some embodiments, the CRBN that is not boundto a reference compound (or unbound CRBN) has a three-dimensionalstructure as determined by x-ray diffraction having the atomiccoordinates set forth in Table 8. Also provided herein is a testcompound identified by this method. In some embodiments, the testcompound induces a CRBN conformational change. In other embodiments, thetest compound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In another embodiment, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first crystal structure of an unbound CRBN, and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of a conformational change (e.g., within the CMA-bindingpocket of the CRBN) or alteration of the properties of a CRBN surface(e.g., on an adjacent region of the protein). In some embodiments, thefirst crystal structure of the unbound CRBN has a three-dimensionalstructure as determined by x-ray diffraction having the atomiccoordinates set forth in Table 8. In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of an unboundCRBN; (b) (i) obtaining a second three-dimensional structure of CRBN andthe test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In some embodiments of the various compositions and methods providedherein, the crystal structure of CRBN is a crystal structure of mouseCRBN. In some embodiments, the crystal structure of CRBN is a crystalstructure of mouse CRBN that is bound to a reference compound. In otherembodiments, the crystal structure of CRBN is a crystal structure ofmouse CRBN that is not bound to a reference compound. In one embodiment,the crystal structure of mouse CRBN that is not bound to a referencecompound has a three-dimensional structure as determined by x-raydiffraction having the atomic coordinates set forth in Table 8. Incertain embodiments of the various compositions and methods providedherein, the crystal structure of CRBN is a crystal structure of humanCRBN. In some embodiments, the crystal structure of CRBN is a crystalstructure of human CRBN that is bound to a reference compound. In otherembodiments, the crystal structure of CRBN is a crystal structure ofhuman CRBN that is not bound to a reference compound. In certainembodiments, the CRBN is further bound to DDB1. In other embodiments ofthe various compositions and methods provided herein, the CMA-bindingpocket of CRBN is an IMiD®-binding pocket.

In a third aspect, provided herein is a method of identifying a testcompound that has a specific downstream biological activity comprising:(a) (i) obtaining a first crystal structure of CRBN and a referencecompound, and (ii) determining a three-dimensional structure of thefirst crystal by x-ray diffraction to obtain a first set of atomiccoordinates; (b) (i) obtaining a second crystal comprising CRBN and thetest compound, and (ii) determining a three-dimensional structure of thesecond crystal by x-ray diffraction to obtain a second set of atomiccoordinates; and (c) comparing said first set of atomic coordinates withsaid second set of atomic coordinates; wherein a difference in atomiccoordinates is indicative of a compound has the specific downstreambiological activity. In some embodiments, the first crystal structure isof a CRBN that is not bound to a reference compound. In one embodiment,the crystal structure of mouse CRBN that is not bound to a referencecompound has a three-dimensional structure as determined by x-raydiffraction having the atomic coordinates set forth in Table 8. In someembodiments, the first set of atomic coordinates and/or said second setof atomic coordinates define a CMA binding domain. In certainembodiments, the difference in atomic coordinates is determined byassessing differences in atomic distances. In some embodiments, themethod further comprises assaying the specific biological activity. Alsoprovided herein is a test compound identified by this method. In someembodiments, the compound induces a CRBN conformational change (e.g.,within the CMA-binding pocket of the CRBN) or otherwise altering theproperties of a CRBN surface. In some embodiments, the test compoundinduces a CRBN conformational change. In other embodiments, the testcompound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In certain embodiments, themethod further comprises administering said compound to a patient,wherein said biological activity is modulated in said patient. Incertain embodiments, the patient has a disease, and wherein one or moresymptoms of said disease are alleviated following said administration.

In a fourth aspect, provided herein is a method of identifying a testcompound that has a specific downstream biological activity comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound has thespecific downstream biological activity. In some embodiments, the firstthree-dimensional structure is of a CRBN that is not bound to areference compound. In one embodiment, the crystal structure of mouseCRBN that is not bound to a reference compound has a three-dimensionalstructure as determined by x-ray diffraction having the atomiccoordinates set forth in Table 8. Also provided herein is a testcompound identified by this method. In some embodiments, the testcompound induces a CRBN conformational change. In other embodiments, thetest compound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In another embodiment, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first crystal structure of CRBN that is not bound toa reference compound, and (ii) determining a three-dimensional structureof the first crystal by x-ray diffraction to obtain a first set ofatomic coordinates; (b) (i) obtaining a second crystal comprising CRBNand the test compound, and (ii) determining a three-dimensionalstructure of the second crystal by x-ray diffraction to obtain a secondset of atomic coordinates; and (c) comparing said first set of atomiccoordinates with said second set of atomic coordinates; wherein adifference in atomic coordinates is indicative of a conformationalchange (e.g., within the CMA-binding pocket of the CRBN) or alterationof the properties of a CRBN surface (e.g., on an adjacent region of theprotein). In certain embodiments, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN that is not bound to a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments of the various methods provided herein, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, thethree-dimensional structure of CRBN that is not bound to a referencecompound has the atomic coordinates set forth in Table 8 as determinedby x-ray diffraction. In some embodiments, the CRBN is further bound toDDB1, Cul4, Roc1, or any combination thereof. In certain embodiments,the CRBN is further bound to DDB1.

In some embodiments of the various compositions and methods providedherein, the CRBN is a mouse CRBN. In certain embodiments of the variouscompositions and methods provided herein, CRBN is a human CRBN. In someembodiments, the CRBN is further bound to DDB1. In other embodiments ofthe various compositions and methods provided herein, the CMA-bindingpocket of CRBN is an IMiD®-binding pocket.

In a fifth aspect, provided herein is a method of identifying a testcompound that has a specific therapeutic efficacy comprising: (a) (i)obtaining a first crystal structure of CRBN and a reference compound,and (ii) determining a three-dimensional structure of the first crystalby x-ray diffraction to obtain a first set of atomic coordinates; (b)(i) obtaining a second crystal comprising CRBN and the test compound,and (ii) determining a three-dimensional structure of the second crystalby x-ray diffraction to obtain a second set of atomic coordinates; and(c) comparing said first set of atomic coordinates with said second setof atomic coordinates; wherein a difference in atomic coordinates isindicative of a compound has the specific therapeutic efficacy. In someembodiments, the first crystal structure is of a CRBN that is not boundto a reference compound. In one embodiment, the first crystal structureof CRBN that is not bound to a reference compound has athree-dimensional structure as determined by x-ray diffraction havingthe atomic coordinates set forth in Table 8. In some embodiments, thefirst set of atomic coordinates and/or said second set of atomiccoordinates define a CMA binding domain. In certain embodiments, thedifference in atomic coordinates is determined by assessing differencesin atomic distances. Also provided herein is a test compound identifiedby this method. In some embodiments, the test compound induces a CRBNconformational change. In other embodiments, the test compound altersthe properties of the CRBN surface. In certain embodiments, theproperties of the CRBN surface are altered by the placement of compoundappendages. In certain embodiments, the conformational change oralteration occurs in a CMA binding pocket of the CRBN. In someembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on W380, W386 and/or W400 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on E377 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on V388 of CRBN. In certain embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on anadjacent region of the protein. In certain embodiments, the methodfurther comprises administering said compound to a patient havingdisease, disorder or condition, wherein one or more symptoms of saiddisease, disorder or condition is alleviated following saidadministration. In some embodiments, the CRBN is further bound to DDB1,Cul4, Roc1, or any combination thereof. In certain embodiments, the CRBNis further bound to DDB1.

In a sixth aspect, provided herein is a method of identifying a testcompound that has a specific downstream biological activity comprising:(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound has thespecific downstream biological activity. In some embodiments, the firstthree-dimensional structure is of a CRBN that is not bound to areference compound. In one embodiment, the first three-dimensionalstructure of CRBN that is not bound to a reference compound has theatomic coordinates set forth in Table 8 as determined by x-raydiffraction. Also provided herein is a test compound identified by thismethod. In some embodiments, the test compound induces a CRBNconformational change. In other embodiments, the test compound altersthe properties of the CRBN surface. In certain embodiments, theproperties of the CRBN surface are altered by the placement of compoundappendages. In certain embodiments, the conformational change oralteration occurs in a CMA binding pocket of the CRBN. In someembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on W380, W386 and/or W400 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on E377 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on V388 of CRBN. In certain embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on anadjacent region of the protein. In an embodiment, the conformationalchange or alteration is assessed by x-ray crystallography. In anotherembodiment, the conformational change or alteration is assessed by amethod comprising (a) (i) obtaining a first crystal structure of CRBNand a reference compound, and (ii) determining a three-dimensionalstructure of the first crystal by x-ray diffraction to obtain a firstset of atomic coordinates; (b) (i) obtaining a second crystal comprisingCRBN and the test compound, and (ii) determining a three-dimensionalstructure of the second crystal by x-ray diffraction to obtain a secondset of atomic coordinates; and (c) comparing said first set of atomiccoordinates with said second set of atomic coordinates; wherein adifference in atomic coordinates is indicative of a conformationalchange (e.g., within the CMA-binding pocket of the CRBN) or alterationof the properties of a CRBN surface (e.g., on an adjacent region of theprotein). In certain embodiments, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN and a reference compound; (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. Inanother embodiment, the conformational change or alteration is assessedby a method comprising (a) (i) obtaining a first crystal structure ofCRBN that is not bound to a reference compound, and (ii) determining athree-dimensional structure of the first crystal by x-ray diffraction toobtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound; (b) (i) obtaining a secondthree-dimensional structure of CRBN and the test compound; and (c)comparing said first three-dimensional structure with said secondthree-dimensional structure; wherein a difference in the first andsecond three-dimensional structures is indicative of a compound thatinduces a CRBN conformational change or alteration. In one embodiment,the first three-dimensional structure of CRBN that is not bound to areference compound has the atomic coordinates set forth in Table 8 asdetermined by x-ray diffraction. In some embodiments, the first and/orsecond three-dimensional structures include a CMA binding domain of theCRBN. In other embodiments, the three-dimensional structure is assessedusing x-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a seventh aspect, provided herein is a method of designing a testcompound based on fit within CMA binding pocket of CRBN, comprising: (a)generating on a computer, three-dimensional structural features of aCRBN having a conformational change in the CMA binding pocket, (b)designing a test compound capable of selectively binding to said CMAbinding pocket, (c) synthesizing said test compound, (d) contacting CRBNwith said synthesized test compound, and (e) determining if said testcompound binds to said CRBN. In certain embodiments, the conformationalchange occurs in a CMA binding pocket of the CRBN. In some embodiments,the conformational change is relative to a CRBN that is not bound to areference compound. In other embodiments, the conformational change isrelative to a CRBN that is bound to a reference compound.

In an eighth aspect, provided herein is a crystal of a complexcomprising CRBN and a CMA, or an analog thereof. Also provided herein isa method of obtaining the crystal, comprising concentrating a purifiedcomplex of the CRBN and the CMA, or analog thereof, and obtaining thecrystal. In certain embodiments, provided herein is a crystal comprisingCRBN. In some embodiments, provided herein is a crystal consisting ofCRBN. In certain embodiments, provided herein is a crystal of a complexcomprising CRBN and DDB1. In some embodiments, provided herein is acrystal of a complex consisting of CRBN and DDB1. In certainembodiments, provided herein is a crystal of a complex comprising CRBNand a CMA, or an analog thereof. In some embodiments, provided herein isa crystal of a complex consisting of CRBN and a CMA or an analogthereof. In certain embodiments, provided herein is a crystal of acomplex comprising CRBN, DDB1, and a CMA, or an analog thereof. In someembodiments, provided herein is a crystal of a complex consisting ofCRBN, DDB1, and a CMA or an analog thereof. Methods of obtaining suchcrystals are also provided herein.

In certain embodiments, the CRBN is bound to DDB1. In some embodiments,the CRBN is bound to Cul4. In other embodiments, the CRBN is bound toRoc1. In some embodiments, the CRBN is bound to DDB1 and Cul4. In otherembodiments, the CRBN is bound to DDB1 and Roc1. In yet otherembodiments, the CRBN is bound to Cul4 and Roc1. In some embodiments,the CRBN is bound to DDB1, Cul4 and Roc1. In certain embodiments, CRBNthat is bound to DDB1, Cul4 and/or Roc1 is a complex with DDB1, Cul4and/or Roc1, respectively. Crystals comprising CRBN and DDB1, Cul4and/or Roc1 are also contemplated, as are methods of obtaining suchcrystals.

In certain embodiments, the CMA is thalidomide. In other embodiments,the CMA is pomalidomide. In some embodiments, the CMA is CC-220. Inother embodiments, the CMA is1-(3-chloro-4-methylphenyl)-3-((2-(2,6-dioxopiperidin-3-yl)-1-oxoisoindolin-5-yl)methyl)urea(CC-885). In certain embodiments, the CMA is a thalidomide analog. Inother embodiments, the CMA is a pomalidomide analog. In someembodiments, the CMA is a CC-220 analog. In other embodiments, the CMAis a CC-885 analog. In other embodiments, the CMA is not thalidomide. Inother embodiments, the CMA is not pomalidomide. In some embodiments, theCMA is not CC-220. In other embodiments, the CMA is not CC-885. In otherembodiments, the CMA is not a thalidomide analog. In other embodiments,the CMA is not a pomalidomide analog. In some embodiments, the CMA isnot a CC-220 analog. In other embodiments, the CMA is not a CC-885analog.

In a ninth aspect, provided herein is a crystal of a complex comprisingCRBN and a test compound, wherein said crystal has a three-dimensionalstructure as determined by x-ray diffraction having the atomiccoordinates set forth in any one of Tables 3, 4, 5, 6 or 7. In oneembodiment, the crystal has a three-dimensional structure as determinedby x-ray diffraction having the atomic coordinates set forth in Table 3.In another embodiment, the crystal has a three-dimensional structure asdetermined by x-ray diffraction having the atomic coordinates set forthin Table 4. In other embodiments, the crystal has a three-dimensionalstructure as determined by x-ray diffraction having the atomiccoordinates set forth in Table 5. In other embodiments, the crystal hasa three-dimensional structure as determined by x-ray diffraction havingthe atomic coordinates set forth in Table 6. In other embodiments, thecomplex has a three-dimensional structure as determined by x-raydiffraction having the atomic coordinates set forth in Table 7. In someembodiments, the crystal further comprises DDB1, Cul4 and/or Roc1. In aspecific embodiment, the complex further comprises DDB1.

In a tenth aspect, provided herein is a crystal of a complex comprisinga CRBN and a test compound, wherein said crystal has a three-dimensionalstructure as determined by x-ray diffraction, wherein saidthree-dimensional structure has the atomic coordinates set forth in anyone of Tables 3, 4, 5, 6 or 7. In one embodiment, the crystal has athree-dimensional structure as determined by x-ray diffraction, whereinsaid three-dimensional structure has the atomic coordinates set forth inTable 3. In another embodiment, the crystal has a three-dimensionalstructure as determined by x-ray diffraction, wherein saidthree-dimensional structure has the atomic coordinates set forth inTable 4. In yet another embodiment, the crystal has a three-dimensionalstructure as determined by x-ray diffraction, wherein saidthree-dimensional structure has the atomic coordinates set forth inTable 5. In yet another embodiment, the crystal has a three-dimensionalstructure as determined by x-ray diffraction, wherein saidthree-dimensional structure has the atomic coordinates set forth inTable 6. In some embodiments, the crystal further comprises DDB1, Cul4and/or Roc1. In a specific embodiment, the crystal further comprisesDDB1. In yet another embodiment, the crystal has a three-dimensionalstructure as determined by x-ray diffraction, wherein saidthree-dimensional structure has the atomic coordinates set forth inTable 7. In some embodiments, the complex further comprises DDB1, Cul4and/or Roc1. In a specific embodiment, the complex further comprisesDDB1.

In certain embodiments of the methods provided herein a complexcomprising CRBN and reference compound has a three-dimensional structureas determined by x-ray diffraction, having the atomic coordinates setforth in any one of Tables 3, 4, 5, 6 or 7. In one embodiment, thethree-dimensional structure has the atomic coordinates set forth inTable 3. In another embodiment, the three-dimensional structure has theatomic coordinates set forth in Table 4. In yet another embodiment, thethree-dimensional structure has the atomic coordinates set forth inTable 5. In yet another embodiment, the three-dimensional structure hasthe atomic coordinates set forth in Table 6. In yet another embodiment,the three-dimensional structure has the atomic coordinates set forth inTable 7. In some embodiments, the complex further comprises DDB1, Cul4and/or Roc1. In a specific embodiment, the complex further comprisesDDB1.

In an eleventh aspect, provided herein is a method of identifying a testcompound that induces a specific biological activity, comprisingcontacting the test compound with CRBN, inducing a CRBN conformationalchange (e.g., within the CMA-binding pocket of the CRBN) or otherwisealtering the properties of a CRBN surface, and assessing conformationalchange or alteration wherein conformational change or alteration isindicative of a specific biological activity. In some embodiments, themethod further comprises assaying the specific biological activity. Alsoprovided herein is a test compound identified by this method. In someembodiments, the test compound induces a CRBN conformational change. Inother embodiments, the test compound induces a CRBN conformationalchange relative to a CRBN contacted with a reference compound. In someembodiments, the test compound induces a CRBN conformational changerelative to a CRBN bound to a reference compound. In other embodiments,the test compound induces a CRBN conformational change relative to aCRBN that is not contacted with a reference compound. In one embodiment,the CRBN that is not contacted with a reference compound has athree-dimensional structure as determined by x-ray diffraction havingthe atomic coordinates set forth in Table 8. In some embodiments, thetest compound induces a CRBN conformational change relative to anunbound CRBN. In other embodiments, the test compound alters theproperties of the CRBN surface. In some embodiments, the test compoundalters the properties of the CRBN surface relative to a CRBN contactedwith a reference compound. In other embodiments, the test compoundalters the properties of the CRBN surface relative to a CRBN bound to areference compound. In some embodiments, the test compound alters theproperties of the CRBN surface relative to a CRBN that is not contactedwith a reference compound. In other embodiments, the test compoundalters the properties of the CRBN surface relative to an unbound CRBN.In certain embodiments, the properties of the CRBN surface are alteredby the placement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In certain embodiments, themethod further comprises administering said compound to a patient,wherein said biological activity is modulated in said patient. Incertain embodiments, the patient has a disease, and wherein one or moresymptoms of said disease are alleviated following said administration.In an embodiment, the conformational change or alteration is assessed byx-ray crystallography. In another embodiment, the conformational changeis assessed by a method comprising (a) (i) obtaining a first crystalstructure of CRBN and a reference compound, and (ii) determining athree-dimensional structure of the first crystal by x-ray diffraction toobtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In some embodiments, the first crystalstructure is of a CRBN that is not bound to a reference compound. In oneembodiment, the first crystal structure of CRBN that is not bound to areference compound has the atomic coordinates set forth in Table 8 asdetermined by x-ray diffraction. In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In other embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound; (b) (i) obtaining a secondthree-dimensional structure of CRBN and the test compound; and (c)comparing said first three-dimensional structure with said secondthree-dimensional structure; wherein a difference in the first andsecond three-dimensional structures is indicative of a compound thatinduces a CRBN conformational change or alteration. In one embodiment,the first three-dimensional structure of CRBN that is not bound to areference compound has the atomic coordinates set forth in Table 8 asdetermined by x-ray diffraction. In some embodiments, the first and/orsecond three-dimensional structures include a CMA binding domain of theCRBN. In other embodiments, the three-dimensional structure is assessedusing x-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a twelfth aspect, provided herein is a method of identifying a testcompound that has a specific therapeutic utility, comprising contactingthe test compound with CRBN, inducing a CRBN conformational change orotherwise altering the properties of the CRBN surface, and assessing theconformational change or alteration, wherein a conformational change oralteration is indicative of the specific therapeutic utility. Alsoprovided herein is a test compound identified by this method. In someembodiments, the test compound induces a CRBN conformational change. Inother embodiments, the test compound induces a CRBN conformationalchange relative to a CRBN contacted with a reference compound. In someembodiments, the test compound induces a CRBN conformational changerelative to a CRBN bound to a reference compound. In other embodiments,the test compound induces a CRBN conformational change relative to aCRBN that is not contacted with a reference compound. In someembodiments, the test compound induces a CRBN conformational changerelative to an unbound CRBN. In other embodiments, the test compoundalters the properties of the CRBN surface. In some embodiments, the testcompound alters the properties of the CRBN surface relative to a CRBNcontacted with a reference compound. In other embodiments, the testcompound alters the properties of the CRBN surface relative to a CRBNbound to a reference compound. In some embodiments, the test compoundalters the properties of the CRBN surface relative to a CRBN that is notcontacted with a reference compound. In other embodiments, the testcompound alters the properties of the CRBN surface relative to anunbound CRBN. In one embodiment, the structure of the unbound CRBN hasthe atomic coordinates set forth in Table 8 as determined by x-raydiffraction. In certain embodiments, the properties of the CRBN surfaceare altered by the placement of compound appendages. In certainembodiments, the conformational change or alteration occurs in a CMAbinding pocket of the CRBN. In some embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on W380,W386 and/or W400 of CRBN. In other embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on E377 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on V388 of CRBN. In certainembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on an adjacent region of the protein. In someembodiments, the method further comprises administering said compound toa patient having a disease, wherein one or more symptoms of said diseaseis alleviated following said administration. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN that is not bound to a reference compound, and(ii) determining a three-dimensional structure of the first crystal byx-ray diffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound; (b) (i) obtaining a secondthree-dimensional structure of CRBN and the test compound; and (c)comparing said first three-dimensional structure with said secondthree-dimensional structure; wherein a difference in the first andsecond three-dimensional structures is indicative of a compound thatinduces a CRBN conformational change or alteration. In one embodiment,the first three-dimensional structure of CRBN that is not bound to areference compound has the atomic coordinates set forth in Table 8 asdetermined by x-ray diffraction. In some embodiments, the first and/orsecond three-dimensional structures include a CMA binding domain of theCRBN. In other embodiments, the three-dimensional structure is assessedusing x-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is bound toDDB1.

In a thirteenth aspect, provided herein is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein), comprising contacting the CRBN with a compound,wherein said CRBN conformational change or alteration results in aspecific biological activity. In one embodiment, the method induces aCRBN conformational change. In a specific embodiment, the CRBNconformational change is within the CMA-binding pocket of the CRBN. Inone embodiment, the CRBN conformational change is relative to a CRBNthat is bound to a reference compound. In one embodiment, the CRBN thatis not bound to a reference compound has a three-dimensional structureas determined by x-ray diffraction having the atomic coordinates setforth in Table 8. In a certain embodiment, the CRBN conformationalchange is relative to an unbound CRBN. In a specific embodiment, theCRBN conformational change is relative to the CRBN prior to contact withthe test compound. In another embodiment, the method induces analteration of the properties of a CRBN surface. In a specificembodiment, the alteration of the properties of a CRBN surface are on anadjacent region of the protein. In one embodiment, the alteration of theproperties of the CRBN surface is relative to a CRBN that is bound to areference compound. In a certain embodiment, the alteration of theproperties of the CRBN surface is relative to an unbound CRBN. In aspecific embodiment, the alteration of the properties of the CRBNsurface is relative to the CRBN prior to contact with the test compound.In some embodiments, the biological activity is a tumoricidal effect. Inother embodiments, the biological activity is an apoptosis effect. Insome embodiments, the biological activity is anti-proliferation. In yetother embodiments, the biological activity is PBMC viability. In someembodiments, the biological activity is toxicity. In certainembodiments, the biological activity is substrate degradation. In oneembodiments, the biological activity is Aiolos degradation. In anotherembodiments, the biological activity is Ikaros degradation. In otherembodiments, the biological activity is an immune-mediated effect. Inanother embodiment, the biological activity is IL-2 induction. In someembodiments, the biological activity is IL-2 repression. In yet otherembodiments, the biological activity is an effect on fetal hemoglobin(HbF). Any combination of one, two, three or more of the aforementionedbiological activities is also contemplated. In certain embodiments, thebiological activity is based on specific cell type categories. In otherembodiments, the biological activity is based on specific tissue typecategories. In yet other embodiments, the biological activity is basedon solid tumors or solid tumor categories. In some embodiments, thebiological activity is based on non-solid tumor categories. In someembodiments, a CRBN conformational change is induced. In otherembodiments, and alteration in the properties of a CRBN surface areinduced. In certain embodiments, the conformational change or alterationoccurs in a CMA binding pocket of the CRBN. In some embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on W380, W386 and/or W400 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on E377 of CRBN. In other embodiments, the conformational changeor alteration in said CMA binding pocket has an effect on V388 of CRBN.In certain embodiments, the conformational change or alteration in saidCMA binding pocket has an effect on an adjacent region of the protein.In an embodiment, the conformational change is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In other embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound (e.g., a CRBN prior to contact withthe test compound); (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In one embodiment, the firstthree-dimensional structure of CRBN that is not bound to a referencecompound has the atomic coordinates set forth in Table 8 as determinedby x-ray diffraction. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a fourteenth aspect, provided herein is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein), comprising contacting the CRBN with a compound,wherein said CRBN conformational change or alteration results in aspecific therapeutic utility. In one embodiment, the method induces aCRBN conformational change. In a specific embodiment, the CRBNconformational change is within the CMA-binding pocket of the CRBN. Inone embodiment, the CRBN conformational change is relative to a CRBNthat is bound to a reference compound. In a certain embodiment, the CRBNconformational change is relative to an unbound CRBN. In a specificembodiment, the CRBN conformational change is relative to the CRBN priorto contact with the test compound. In another embodiment, the methodinduces an alteration of the properties of a CRBN surface. In a specificembodiment, the alteration of the properties of a CRBN surface are on anadjacent region of the protein. In one embodiment, the alteration of theproperties of the CRBN surface is relative to a CRBN that is bound to areference compound. In a certain embodiment, the alteration of theproperties of the CRBN surface is relative to an unbound CRBN. In aspecific embodiment, the alteration of the properties of the CRBNsurface is relative to the CRBN prior to contact with the test compound.In some embodiments, the unbound CRBN or the CRBN prior to contact withthe test compound has a three-dimensional structure as determined byx-ray diffraction having the atomic coordinates set forth in Table 8. Insome embodiments, the therapeutic utility is based on solid tumors orsolid tumor categories. In other embodiments, the therapeutic utility isbased on non-solid tumor categories. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein). In another embodiment, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first crystal structure of CRBN that is not bound toa reference compound (e.g., a CRBN prior to contact with the testcompound), and (ii) determining a three-dimensional structure of thefirst crystal by x-ray diffraction to obtain a first set of atomiccoordinates; (b) (i) obtaining a second crystal comprising CRBN and thetest compound, and (ii) determining a three-dimensional structure of thesecond crystal by x-ray diffraction to obtain a second set of atomiccoordinates; and (c) comparing said first set of atomic coordinates withsaid second set of atomic coordinates; wherein a difference in atomiccoordinates is indicative of a conformational change (e.g., within theCMA-binding pocket of the CRBN) or alteration of the properties of aCRBN surface (e.g., on an adjacent region of the protein). In certainembodiments, the conformational change or alteration is assessed by amethod comprising (a) (i) obtaining a first three-dimensional structureof CRBN that is not bound to a reference compound (e.g., a CRBN prior tocontact with the test compound); (b) (i) obtaining a secondthree-dimensional structure of CRBN and the test compound; and (c)comparing said first three-dimensional structure with said secondthree-dimensional structure; wherein a difference in the first andsecond three-dimensional structures is indicative of a compound thatinduces a CRBN conformational change (e.g., within the CMA-bindingpocket of the CRBN) or alteration of the properties of a CRBN surface(e.g., on an adjacent region of the protein). In one embodiment, thefirst three-dimensional structure of CRBN that is not bound to areference compound has the atomic coordinates set forth in Table 8 asdetermined by x-ray diffraction. In some embodiments, the first and/orsecond three-dimensional structures include a CMA binding domain of theCRBN. In other embodiments, the three-dimensional structure is assessedusing x-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a fifteenth aspect, provided herein is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein), comprising contacting the CRBN with a testcompound, wherein said CRBN conformational change or alteration resultsin a different substrate specificity as compared to the substratespecificity of a CRBN that is contacted with a reference compound. Alsoprovided herein is a method of inducing a CRBN conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein), comprising contacting the CRBN with a test compound, whereinsaid CRBN conformational change or alteration results in a differentsubstrate specificity as compared to the substrate specificity of anunbound CRBN (e.g., a CRBN prior to contact with the test compound). Inone embodiment, the method induces a CRBN conformational change. In aspecific embodiment, the CRBN conformational change is within theCMA-binding pocket of the CRBN. In one embodiment, the CRBNconformational change is relative to a CRBN that is bound to a referencecompound. In a certain embodiment, the CRBN conformational change isrelative to an unbound CRBN. In a specific embodiment, the CRBNconformational change is relative to the CRBN prior to contact with thetest compound. In another embodiment, the method induces an alterationof the properties of a CRBN surface. In a specific embodiment, thealteration of the properties of a CRBN surface are on an adjacent regionof the protein. In one embodiment, the alteration of the properties ofthe CRBN surface is relative to a CRBN that is bound to a referencecompound. In a certain embodiment, the alteration of the properties ofthe CRBN surface is relative to an unbound CRBN. In a specificembodiment, the alteration of the properties of the CRBN surface isrelative to the CRBN prior to contact with the test compound. In someembodiments, the unbound CRBN or the CRBN prior to contact with the testcompound has a three-dimensional structure as determined by x-raydiffraction having atomic coordinates set forth in Table 8. In someembodiments, a CRBN conformational change is induced. In otherembodiments, an alteration of the properties of a CRBN surface areinduced. In certain embodiments, the properties of the CRBN surface arealtered by the placement of compound appendages. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN. In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN that is not bound to a reference compound(e.g., a CRBN prior to contact with the test compound), and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound (e.g., a CRBN prior to contact withthe test compound); (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In one embodiment, the firstthree-dimensional structure of CRBN that is not bound to a referencecompound has the atomic coordinates set forth in Table 8 as determinedby x-ray diffraction. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a sixteenth aspect, provided herein is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein), comprising contacting the CRBN with a testcompound. In one embodiment, the method induces a CRBN conformationalchange. In a specific embodiment, the CRBN conformational change iswithin the CMA-binding pocket of the CRBN. In one embodiment, the CRBNconformational change is relative to a CRBN that is bound to a referencecompound. In a certain embodiment, the CRBN conformational change isrelative to an unbound CRBN. In a specific embodiment, the CRBNconformational change is relative to the CRBN prior to contact with thetest compound. In another embodiment, the method induces an alterationof the properties of a CRBN surface. In a specific embodiment, thealteration of the properties of a CRBN surface are on an adjacent regionof the protein. In one embodiment, the alteration of the properties ofthe CRBN surface is relative to a CRBN that is bound to a referencecompound. In a certain embodiment, the alteration of the properties ofthe CRBN surface is relative to an unbound CRBN. In a specificembodiment, the alteration of the properties of the CRBN surface isrelative to the CRBN prior to contact with the test compound. In oneembodiment, the unbound CRBN or the CRBN prior to contact with the testcompound has a first three-dimensional structure as determined by x-raydiffraction having the atomic coordinates set forth in Table 8. In someembodiments, said CRBN conformational change or alteration comprises aconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein) that is different than the conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein) contacted with a reference compound. In some embodiments, theCRBN conformational change or alteration results in a differentbiological activity. In some embodiments, the CRBN conformational changeor alteration results in a different therapeutic utility. In otherembodiments, the CRBN conformational change or alteration results in adifferent substrate specificity. In some embodiments, a CRBNconformational change is induced. In other embodiments, an alteration ofthe properties of a CRBN surface are induced. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN. In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN that is not bound to a reference compound(e.g., a CRBN prior to contact with the test compound), and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound (e.g., a CRBN prior to contact withthe test compound); (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In one embodiment, the firstthree-dimensional structure of CRBN that is not bound to a referencecompound has the atomic coordinates set forth in Table 8 as determinedby x-ray diffraction. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a seventeenth aspect, provided herein is a method of inducing abiological activity in a cell comprising CRBN, comprising contactingsaid cell with a test compound, wherein said compound induces aconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein) of said CRBN, and wherein said CRBNconformational change or alteration is as compared to a referencecompound, and wherein the conformational change or alteration results insaid biological activity. Also provided herein is a method of inducing abiological activity in a cell comprising CRBN, comprising contactingsaid cell with a test compound, wherein said compound induces aconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein) of said CRBN, and wherein said CRBNconformational change or alteration is as compared to an unbound CRBN(e.g., a CRBN prior to contact with the test compound), and wherein theconformational change or alteration results in said biological activity.In one embodiment, the method induces a CRBN conformational change. In aspecific embodiment, the CRBN conformational change is within theCMA-binding pocket of the CRBN. In one embodiment, the CRBNconformational change is relative to a CRBN that is bound to a referencecompound. In a certain embodiment, the CRBN conformational change isrelative to an unbound CRBN. In a specific embodiment, the CRBNconformational change is relative to the CRBN prior to contact with thetest compound. In one embodiment, the unbound CRBN or the CRBN prior tocontact with the test compound has a first three-dimensional structureas determined by x-ray diffraction having the atomic coordinates setforth in Table 8. In another embodiment, the method induces analteration of the properties of a CRBN surface. In a specificembodiment, the alteration of the properties of a CRBN surface are on anadjacent region of the protein. In one embodiment, the alteration of theproperties of the CRBN surface is relative to a CRBN that is bound to areference compound. In a certain embodiment, the alteration of theproperties of the CRBN surface is relative to an unbound CRBN. In aspecific embodiment, the alteration of the properties of the CRBNsurface is relative to the CRBN prior to contact with the test compound.In some embodiments, the biological activity is a tumoricidal effect. Inother embodiments, the biological activity is an apoptosis effect. Insome embodiments, the biological activity is anti-proliferation. In yetother embodiments, the biological activity is PBMC viability. In someembodiments, the biological activity is toxicity. In certainembodiments, the biological activity is substrate degradation. In oneembodiments, the biological activity is Aiolos degradation. In anotherembodiments, the biological activity is Ikaros degradation. In otherembodiments, the biological activity is an immune-mediated effect. Inanother embodiment, the biological activity is IL-2 induction. In someembodiments, the biological activity is IL-2 repression. In yet otherembodiments, the biological activity is a HbF effect. Any combination ofone, two, three or more of the aforementioned biological activities isalso contemplated. In certain embodiments, the biological activity isbased on specific cell type categories. In other embodiments, thebiological activity is based on specific tissue type categories. In yetother embodiments, the biological activity is based on solid tumors orsolid tumor categories. In some embodiments, the biological activity isbased on non-solid tumor categories. In some embodiments, a CRBNconformational change is induced. In other embodiments, an alteration ofthe properties of a CRBN surface are induced. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN. In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN and a reference compound; (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. Inanother embodiment, the conformational change or alteration is assessedby a method comprising (a) (i) obtaining a first crystal structure ofCRBN that is not bound to a reference compound (e.g., a CRBN prior tocontact with the test compound), and (ii) determining athree-dimensional structure of the first crystal by x-ray diffraction toobtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN that is not bound to a referencecompound (e.g., a CRBN prior to contact with the test compound); (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. In oneembodiment, the unbound CRBN or the CRBN prior to contact with the testcompound has a first three-dimensional structure as determined by x-raydiffraction having the atomic coordinates set forth in Table 8. In someembodiments, the first and/or second three-dimensional structuresinclude a CMA binding domain of the CRBN. In other embodiments, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof. In aspecific embodiment, the CRBN is further bound to DDB1.

In an eighteenth aspect, provided herein is a method of treating oralleviating one or more symptoms of a CRBN-mediated disease or disorderin a patient, comprising administering a test compound to the subject,wherein said test compound induces a conformational change (e.g., withinthe CMA-binding pocket of the CRBN) or alteration of the properties of aCRBN surface (e.g., on an adjacent region of the protein), and whereinsaid CRBN conformational change or alteration is as compared to areference compound, and wherein said CRBN conformational change oralteration results in treatment or alleviation of one or more symptomsof said disease or disorder. Also provided herein is a method oftreating or alleviating one or more symptoms of a CRBN-mediated diseaseor disorder in a patient, comprising administering a test compound tothe subject, wherein said test compound induces a conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein), and wherein said CRBN conformational change or alteration isas compared to an unbound CRBN (e.g., a CRBN prior to contact with thetest compound), and wherein said CRBN conformational change oralteration results in treatment or alleviation of one or more symptomsof said disease or disorder. In one embodiment, the method induces aCRBN conformational change. In a specific embodiment, the CRBNconformational change is within the CMA-binding pocket of the CRBN. Inone embodiment, the CRBN conformational change is relative to a CRBNthat is bound to a reference compound. In a certain embodiment, the CRBNconformational change is relative to an unbound CRBN. In a specificembodiment, the CRBN conformational change is relative to the CRBN priorto contact with the test compound. In one embodiment, the unbound CRBNor the CRBN prior to contact with the test compound has a firstthree-dimensional structure as determined by x-ray diffraction havingthe atomic coordinates set forth in Table 8. In another embodiment, themethod induces an alteration of the properties of a CRBN surface. In aspecific embodiment, the alteration of the properties of a CRBN surfaceare on an adjacent region of the protein. In one embodiment, thealteration of the properties of the CRBN surface is relative to a CRBNthat is bound to a reference compound. In a certain embodiment, thealteration of the properties of the CRBN surface is relative to anunbound CRBN. In a specific embodiment, the alteration of the propertiesof the CRBN surface is relative to the CRBN prior to contact with thetest compound. In certain embodiments, the disease or disorder is acancer or tumor. In some embodiments, a CRBN conformational change isinduced. In other embodiments, an alteration of the properties of a CRBNsurface are induced. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN that is not bound to a reference compound(e.g., a CRBN prior to contact with the test compound), and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound (e.g., a CRBN prior to contact withthe test compound); (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In one embodiment, the firstcrystal structure of CRBN has a first three-dimensional structure asdetermined by x-ray diffraction having the atomic coordinates set forthin Table 8. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1. In some embodiments provided herein is the above-described testcompound for use in a method of treating or alleviating one or moresymptoms of a CRBN-mediated disease or disorder in a patient.

In a nineteenth aspect, provided herein is a composition comprising aCRBN and a test compound, wherein said CRBN has a conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein) as compared to a reference compound. Also provided herein is acomposition comprising a CRBN and a test compound, wherein said CRBN hasa conformational change (e.g., within the CMA-binding pocket of theCRBN) or alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein) as compared to an unbound CRBN (e.g., aCRBN prior to contact with the test compound). In one embodiment, theCRBN has a conformational change. In a specific embodiment, the CRBNconformational change is within the CMA-binding pocket of the CRBN. Inanother embodiment, the CRBN has an alteration of the properties of aCRBN surface. In a specific embodiment, the alteration of the propertiesof a CRBN surface are on an adjacent region of the protein. In certainembodiments, the conformational change or alteration occurs in a CMAbinding pocket of the CRBN. In some embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on W380,W386 and/or W400 of CRBN. In other embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on E377 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on V388 of CRBN. In certainembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on an adjacent region of the protein. In anembodiment, the conformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN that is not bound to a reference compound(e.g., a CRBN prior to contact with the test compound), and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN that isnot bound to a reference compound (e.g., a CRBN prior to contact withthe test compound); (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In one embodiment, the firstthree-dimensional structure of CRBN as determined by x-ray diffractionhas atomic coordinates set forth in Table 8. In some embodiments, thefirst and/or second three-dimensional structures include a CMA bindingdomain of the CRBN. In other embodiments, the three-dimensionalstructure is assessed using x-ray crystallography, NMR spectroscopy,dual polarization interferometry, vibrational spectroscopy, orcryo-elecron microscopy. In some embodiments, the CRBN is further boundto DDB1, Cul4, Roc1, or any combination thereof. In a specificembodiment, the CRBN is further bound to DDB1.

In a twentieth aspect, provided herein is a compound that induces a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein) upon contact with said CRBN, as compared to theconformational change or alteration as compared to a reference compound.Also provided herein is a compound that induces a CRBN conformationalchange (e.g., within the CMA-binding pocket of the CRBN) or alterationof the properties of a CRBN surface (e.g., on an adjacent region of theprotein) upon contact with said CRBN, as compared to the conformationalchange or alteration as compared to an unbound CRBN (e.g., prior tocontact with the compound). In one embodiment, the unbound CRBN has athree-dimensional structure as determined by x-ray diffraction havingatomic coordinates set forth in Table 8. In one embodiment, the compoundinduces a CRBN conformational change. In a specific embodiment, the CRBNconformational change is within the CMA-binding pocket of the CRBN. Inanother embodiment, the compound induces an alteration of the propertiesof a CRBN surface. In a specific embodiment, the alteration of theproperties of a CRBN surface are on an adjacent region of the protein.In some embodiments, the CRBN conformational change or alterationresults in a different biological activity. In some embodiments, theCRBN conformational change or alteration results in a differenttherapeutic utility. In other embodiments, the CRBN conformationalchange or alteration results in a different substrate specificity. Insome embodiments, a CRBN conformational change is induced. In otherembodiments, an alteration of the properties of a CRBN surface areinduced. In certain embodiments, the conformational change or alterationoccurs in a CMA binding pocket of the CRBN. In some embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on W380, W386 and/or W400 of CRBN In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on E377 of CRBN. In other embodiments, the conformational changeor alteration in said CMA binding pocket has an effect on V388 of CRBN.In certain embodiments, the conformational change or alteration in saidCMA binding pocket has an effect on an adjacent region of the protein.In an embodiment, the conformational change or alteration is assessed byx-ray crystallography. In another embodiment, the conformational changeor alteration is assessed by a method comprising (a) (i) obtaining afirst crystal structure of CRBN and a reference compound, and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In another embodiment, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first crystal structure of CRBN that is not bound toa reference compound (e.g., a CRBN prior to contact with the testcompound), and (ii) determining a three-dimensional structure of thefirst crystal by x-ray diffraction to obtain a first set of atomiccoordinates; (b) (i) obtaining a second crystal comprising CRBN and thetest compound, and (ii) determining a three-dimensional structure of thesecond crystal by x-ray diffraction to obtain a second set of atomiccoordinates; and (c) comparing said first set of atomic coordinates withsaid second set of atomic coordinates; wherein a difference in atomiccoordinates is indicative of conformational change (e.g., within theCMA-binding pocket of the CRBN) or alteration of the properties of aCRBN surface (e.g., on an adjacent region of the protein). In certainembodiments, the conformational change or alteration is assessed by amethod comprising (a) (i) obtaining a first three-dimensional structureof CRBN that is not bound to a reference compound (e.g., a CRBN prior tocontact with the test compound); (b) (i) obtaining a secondthree-dimensional structure of CRBN and the test compound; and (c)comparing said first three-dimensional structure with said secondthree-dimensional structure; wherein a difference in the first andsecond three-dimensional structures is indicative of a compound thatinduces a CRBN conformational change or alteration. In one embodiment,the first three-dimensional structure of CRBN that is not bound to areference compound has the atomic coordinates set forth in Table 8 asdetermined by x-ray diffraction. In some embodiments, the first and/orsecond three-dimensional structures include a CMA binding domain of theCRBN. In other embodiments, the three-dimensional structure is assessedusing x-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof. In a specific embodiment, the CRBN is further boundto DDB1.

In a twenty-first aspect, provided herein is a complex comprising a CRBNand test compound, wherein said CRBN has a conformational change (e.g.,within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein) as compared to a conformational change of said CRBN contactedwith a reference compound. Also provided herein is a complex comprisinga CRBN and test compound, wherein said CRBN has a conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein) as compared to a conformational change of an unbound CRBN(e.g., a CRBN prior to contact with the test compound). In oneembodiment, the CRBN has a conformational change. In a specificembodiment, the CRBN has a conformational change within the CMA-bindingpocket of the CRBN. In another embodiment, the CRBN has an alteration ofthe properties of a CRBN surface. In a specific embodiment, thealteration of the properties of a CRBN surface are on an adjacent regionof the protein. In certain embodiments, the conformational change oralteration occurs in a CMA binding pocket of the CRBN. In someembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on W380, W386 and/or W400 of CRBN In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on E377 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on V388 of CRBN. In certain embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on anadjacent region of the protein. In an embodiment, the conformationalchange or alteration is assessed by x-ray crystallography. In anotherembodiment, the conformational change or alteration is assessed by amethod comprising (a) (i) obtaining a first crystal structure of CRBNand a reference compound, and (ii) determining a three-dimensionalstructure of the first crystal by x-ray diffraction to obtain a firstset of atomic coordinates; (b) (i) obtaining a second crystal comprisingCRBN and the test compound, and (ii) determining a three-dimensionalstructure of the second crystal by x-ray diffraction to obtain a secondset of atomic coordinates; and (c) comparing said first set of atomiccoordinates with said second set of atomic coordinates; wherein adifference in atomic coordinates is indicative of conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein). In certain embodiments, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN and a reference compound; (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. Inanother embodiment, the conformational change or alteration is assessedby a method comprising (a) (i) obtaining a first crystal structure ofCRBN that is not bound to a reference compound (e.g., a CRBN prior tocontact with the test compound), and (ii) determining athree-dimensional structure of the first crystal by x-ray diffraction toobtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN that is not boundto a reference compound (e.g., a CRBN prior to contact with the testcompound); (b) (i) obtaining a second three-dimensional structure ofCRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In one embodiment, the firstthree-dimensional structure of CRBN that is not bound to a referencecompound has a three-dimensional structure as determined by x-raydiffraction having atomic coordinates set forth in Table 8. In someembodiments, the first and/or second three-dimensional structuresinclude a CMA binding domain of the CRBN. In other embodiments, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof. In aspecific embodiment, the CRBN is further bound to DDB1.

In a twenty-second aspect, provided herein is a method of identifying asubstrate ubiquitinated by a E3 ubiquitination ligase complex comprisingCRBN, said method comprising: (i) contacting said CRBN with a compoundthat induces a conformational change (e.g., within the CMA-bindingpocket of the CRBN) or alteration of the properties of a CRBN surface(e.g., on an adjacent region of the protein), wherein said CRBNconformational change or alteration results in ubiquitination of saidsubstrate, (ii) assaying for ubiquitination of one or more substrates,and (iii) identifying said one or more ubiquitinated substrates; whereinsaid substrate is not ubiquitinated by said E3 ubiquitination ligasecomplex in the absence of said compound. Also provided is a substrateidentified by this method. In some embodiments, the conformationalchange or alteration is as compared to the CMA binding pocket when theCRBN is contacted with a reference compound. In some embodiments, theconformational change or alteration is as compared to the CMA bindingpocket of an unbound CRBN (e.g., a CRBN prior to contact with thecompound that induce a conformational change or alteration of theproperties of the CRBN surface). In some embodiments, a CRBNconformational change is induced. In other embodiments, an alteration ofthe properties of a CRBN surface are induced. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN. In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN that is not bound to a reference compound(e.g., a CRBN prior to contact with the test compound), and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure CRBN that is notbound to a reference compound (e.g., a CRBN prior to contact with thetest compound); (b) (i) obtaining a second three-dimensional structureof CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In one embodiment, the firstthree-dimensional structure of CRBN that is not bound to a referencecompound has a three-dimensional structure as determined by x-raydiffraction having atomic coordinates set forth in Table 8. In someembodiments, the first and/or second three-dimensional structuresinclude a CMA binding domain of the CRBN. In other embodiments, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof. In aspecific embodiment, the CRBN is further bound to DDB1.

In a twenty-third aspect, provided herein is a method of recruiting asubstrate for ubiquitination by a E3 ubiquitination ligase complexcomprising CRBN, said method comprising contacting said CRBN with acompound that induces a conformational change of the CRBN (e.g., withinthe CMA-binding pocket of the CRBN) or alteration of the properties of aCRBN surface (e.g., on an adjacent region of the protein), wherein saidCRBN conformational change or alteration results in recruitment andubiquitination of said substrate; and wherein said substrate is notubiquitinated by said E3 ubiquitination ligase complex in the absence ofsaid compound. In some embodiments, the induction of the conformationalchange or alteration is as compared of the CRBN (e.g., the CMA bindingpocket of CRBN) or CRBN surface when the CRBN is contacted with areference compound. In other embodiments, the induction of theconformational change or alteration is as compared of the CRBN (e.g.,the CMA binding pocket of CRBN) or CRBN surface when the CRBN is unbound(e.g., prior to contact with the compound). In some embodiments, a CRBNconformational change is induced. In other embodiments, an alteration ofthe properties of a CRBN surface are induced. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In certain embodiments of the various compositions and methods providedherein, the crystal comprises a full-length CRBN protein. In otherembodiments of the various compositions and methods provided herein, thecrystal comprises a portion of the CRBN protein. In certain embodiments,the portion of the CRBN protein is a CMA binding domain. That is, incertain embodiments provided herein, methods that comprise obtaining acrystal comprising CRBN and a compound, includes without limitationobtaining a crystal comprising a CMA binding domain (i.e., not thefull-length CRBN) and a compound. In some embodiments, the crystalcomprises the thalidomide binding domain (TBD) (a type of a CMA-bindingdomain) of human CRBN (amino acids 319-427 (SEQ ID NO: 5)). In otherembodiments, the crystal comprises the TBD of mouse CRBN (amino acids322-430 (SEQ ID NO: 6)). Crystals comprising other CMA-binding domainsare also contemplated.

In other embodiments of the various compositions and methods providedherein, the three-dimensional structure comprises a full-length CRBNprotein. In other embodiments of the various compositions and methodsprovided herein, the three-dimensional structure comprises a portion ofthe CRBN protein. In certain embodiments, the portion of the CRBNprotein is a CMA-binding domain. That is, in certain embodimentsprovided herein, methods that comprise obtaining a three-dimensionalstructure of a complex comprising CRBN and a compound, includes withoutlimitation obtaining a three-dimensional structure of a complexcomprising a CMA binding domain (i.e., not the full-length CRBN) and acompound. In some embodiments, the crystal comprises TBD of human CRBN(amino acids 319-427 (SEQ ID NO: 5)). In other embodiments, the crystalcomprises the TBD of mouse CRBN (amino acids 322-430 (SEQ ID NO: 6)).Three-dimensional structures comprising other CMA-binding domains arealso contemplated.

Exemplary methods of obtaining the crystal structure, e.g., of a CRBN(or a CMA-binding domain thereof), either alone or complexed with a CMA,are provided elsewhere herein.

In certain embodiments of the various compositions and methods providedherein, the atomic coordinates are set forth in Table 3. In otherembodiments of the various compositions and methods provided herein, theatomic coordinates are set forth in Table 4. In some embodiments of thevarious compositions and methods provided herein, the atomic coordinatesare set forth in Table 5. In some embodiments of the variouscompositions and methods provided herein, the atomic coordinates are setforth in Table 6. In some embodiments of the various compositions andmethods provided herein, the atomic coordinates are set forth in Table7.

In certain embodiments of the various compositions and methods providedherein, the three-dimensional structure is reflected by the atomiccoordinates set forth in Table 3. In other embodiments of the variouscompositions and methods provided herein, the three-dimensionalstructure is reflected by the atomic coordinates set forth in Table 4.In some embodiments of the various compositions and methods providedherein, the three-dimensional structure is reflected by the atomiccoordinates set forth in Table 5. In some embodiments of the variouscompositions and methods provided herein, the three-dimensionalstructure is reflected by the atomic coordinates set forth in Table 6.In some embodiments of the various compositions and methods providedherein, the three-dimensional structure is reflected by the atomiccoordinates set forth in Table 7. In some embodiments of the variouscompositions and methods provided herein, the three-dimensionalstructure is reflected by the atomic coordinates set forth in Table 8.

In certain embodiments of the various compositions and methods providedherein, the three-dimensional structure is provided in any one of thefigures, including, for example, FIGS. 12-18 or 20. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 12. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 13. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 14. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 15. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 16. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 17. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 18. In some embodimentsof the various compositions and methods provided herein, thethree-dimensional structure is provided in FIG. 20.

4. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts the differences in protein homeostasis followingtreatment with a CMA due to altered protein ubiquitination anddegradation.

FIG. 2 depicts crystals of CRBN complexed with a Apo (negative control),thalidomide, pomalidomide, CC-220, or CC-885. Identical projections ofthe CMA binding surfaces of CRBN show protein conformational changes.

FIGS. 3A-3B depicts the crystal structure of CC-220 in CRBN, in whichthe drug can act as a “molecular glue” or bridge with a substrate, suchas a CRBN-associated protein. FIG. 3A: Unbound mouse CRBN prior toCC-220 binding, and FIG. 3B: mouse CRBN in complex with CC-220.

FIG. 4 depicts a complex of CRBN and CC-220 or thalidomide, and a 50°rotation of “pthalimide” ring in CC-220 relative to thalidomide orpomalidomide is observed.

FIGS. 5A-B depict lenalidomide competes with Compound A and1-(3-chloro-4-methylphenyl)-3-((2-(2,6-dioxopiperidin-3-yl)-1-oxoisoindolin-5-yl)methyl)urea(CC-885) for CRBN. FIGS. 5A-B show that co-treatment of lenalidomidewith either Compound A or CC-885 blocks the anti-proliferative effectsof either drug through competition of binding to the CRBN complex inboth ABC and GCB DLBCL. Co-culture of Lenalidomide with either CC-122 orCC-885 dampens the activity of these compounds as they target the samebinding pocket with relative affinity.

FIG. 6 shows that CC-885 induced early apoptosis in the multiple myeloma(MM) cell line H929.

FIG. 7 shows that CC-885 is potent across a panel of solid tumor lines.

FIG. 8 shows that CC-885 binds CRBN protein MM cell extracts.

FIG. 9 shows that CRBN is required for the anti-proliferative activityof CC-885 in myeloma cells.

FIG. 10 shows that CRBN is required for the anti-proliferative activityof CC-885 in myeloma cells.

FIG. 11 shows that CRBN is required for both inhibition andpro-apoptotic activity of CC-885 in the MDA-MB-213 breast cancer cells.

FIG. 12 shows the structure of human cereblon in complex with humanDDB1. Lenalidomide binds the thalidomide binding domain (TBD; sometimesalso referred to as IMID®-binding domain (IBD) herein) (a type ofCMA-binding domain) on the opposing face to the DDB1 binding motif. TheCereblon Lon-like domain (LLD) is shown in yellow. The TBD is shown inblue with the region deleted in a human polymorphism shown in red. DDB1is shown in green with a grey surface. The DDB1 beta propeller domainsare labeled BPA, BPB and BPC. Lenalidomide is shown as yellow sticks,and the zinc ion as a grey sphere.

FIG. 13 shows the structural superposition of cereblon with Bacillussubtilis Ion protease (red, PDB code 3M65. The cereblon Ion-like domain(LLD) is shown in yellow and the TBD is shown in blue. The DDB1 bindingmotif is inserted into the LLD, while the TBD exhibits no similarity toIon protease and occurs at the C-terminus.

FIG. 14 shows the structural superposition of cereblon:DDB1 (yellow andgreen, respectively) with DDB2:DDB1 (DDB2 shown in blue, DDB1 omitted).DDB1-binding is typically mediated by a helix-turn-helix motif such ashelices c and d, which interact with the DDB1 beta-propellar C (BPC)domain. CRBN makes interactions with DDB1 BPC, but also places helix eto interact with the DDB1 beta-propeller A (BDA) domain.

FIG. 15 shows the TBD of human cereblon. The IMiD® binding domain isshown in blue, lenalidomide is shown in yellow sticks, the Lon-likedomain is shown in the background in yellow. The IMiD® binding pocket iscomposed of 3 tryptophan residues: W380, W386 and W400. Three hydrogenbonds between the TBD and lenalidomide are shown as a dotted line to theprotein backbone at H378 and W380 and to the sidechain of H378. The zincbinding site is shown as a grey sphere, and is approximately 18 Å fromlenalidomide. The beta sheet region which varies in the other structuresis marked by a ‘β’.

FIG. 16 shows the murine TBD in complex with thalidomide.

FIG. 17 shows the murine TBD in complex with pomalidomide.

FIG. 18 shows the structural superposition of cereblon TBD (blue) withmethionine sulfoxide reductase (green) and RIG-I (magenta).

FIG. 19 shows the sequence alignment differences mapped onto the surfaceof the IMiD®-binding domain of cereblon (Homo sapiens has a sequence ofSEQ ID NO: 17; Macaca has a sequence of SEQ ID NO: 18; Mus has asequence of SEQ ID NO: 19; Rattus has a sequence of SEQ ID NO: 20;Drosophila has a sequence of SEQ ID NO: 21; Glycine max has a sequenceof SEQ ID NO: 22). Conserved residues relative to the human protein areshown in red, conservative changes are shown in orange, nonconservativechanges are shown in white. The IMiD® binding pocket is indicated by ablue arrow. Tryptophan residues directly involved in IMiD® binding areshown in bold in the sequence alignment. The IMiD®-binding pocketdemonstrates extremely high conservation across plant and animalkingdoms.

FIG. 20 shows the TBD of murine cereblon showing the crystal contactsformed between protein monomers, bridged by thalomide molecules.

FIGS. 21A-21C show a CRBN-binding assay with thalidomide enantiomers.FIG. 21A: Competitive elution assay using thalidomide-immobilized beadscoupled with racemic thalidomide. Beads were washed three times with0.5% NP-40 lysis buffer and bound proteins were eluted with wash buffercontaining 1 mM S-, R-thalidomide (S-Thal or R-Thal) or 0.1% DMSO forthe indicated time. The eluate was then analyzed by SDS-PAGE andimmunoblotting (IB). FIG. 21B: Same as in FIG. 21A, but eluted with abuffer solution containing the indicated concentrations of SorR-thalidomide (S- or R-Thal). FIG. 21C: Inhibitory effects ofthalidomide enantiomers on auto-ubiquitylation of FH-CRBN was detectedin the presence of MG132. Cells were treated with DMSO or the indicatedconcentrations of S- or R-thalidomide for 4 hours prior to harvesting.

FIG. 22A-22C shows Phylogenetically conserved tryptophan residues (W386and W4000) confer binding of CRBN to IMiD® and are required for IMiD®function in vivo. FIG. 22A: Cell lines re-expressing full-length CRBNwild-type. W386A or W400A mutants were tested for the ability to bindIMiD® compounds. Assay was repeated at least three times. RepresentativeWestern blot of representative experiment is shown. FIG. 22B: Cellproliferation assay of DF15 (sensitive). DF15R (resistant; CRBN^(null)),CRBNWT, CRBNW386A; CRBN400 cells treated with a dose response ofpomalidomide. Assays were done in triplicate and error barsrepresentative s.d. Data for each cell line was normalized to treatmentwith vehicle (DMSO). FIG. 22C: Western blots of key downstream effectorsof IMiD® resistance.

FIGS. 23A-23B show the effects of E377V mutation on CRBN activity invivo.

FIG. 23A: Cell lines re-expressing RFP or full length CRBN wild type orE377V mutant were tested for the ability of CRBN proteins to bind IMiD®compounds. Assay was repeated at least three times. RepresentativeWestern blot of representative experiment is shown. FIG. 23B: Cellproliferation assay of DF15 (sensitive), DF15R (resistant; CRBN^(null)),CRBN^(WT), CRBN^(E377V) cells treated with a dose response ofpomalidomide. Assays were done in triplicate and error bars represents.d. Data for each cell line was normalized to treatment with vehicle(DMSO). The insert shows Western blots of Aiolos and 3-actin.

FIGS. 24A-24D show CRBN in lysates from DF15. FIG. 24A: Immunoblotanalysis of CRBN in lysates from DF15, DF15R, DF15R RFP (RFP ctrl),DF15R CRBN^(WT) (CRBN wt), DF15R CRBN^(W386A) and CRBN^(W400A) cells.FIG. 24B: CRBN analysis in DF15 and DF15R and DF15R-derived cell linesby immunohistochemistry confocal microscopy. Images were obtained usinga Nikon E800 confocal microscope at a 40× magnification. CRBN signal isshown in cytoplasm and nucleus of the calls. DAPI staining identifiesthe nucleus of cells (darker staining). FIG. 24C: Immunoblot ofanti-FLAG immunoprecipitation from cell extracts using FLAG-tagged CRBNproteins. FIG. 24D: Immunoblot of thalidomide analog affinity beadbinding to CRBN in DF15, DF15R and DF15R CRBN^(WT) cell extracts. Lanedescription in order (left to right): In=DF15 input prior to beadpurification; V=DF15 extract control (1% DMSO preincubation); Len=DF15Rextract preincubated with lenalidomide (30 μM); Pom=DF15R extractpreincubated with pomalidomide (30 μM); In=DF15R CRBN^(WT) input priorto bead purification; V=DF15R CRBN^(WT) control (1% DMSO preincubation);Len=DF15R CRBN^(WT) extract preincubated with lenalidomide (30 μM);Pom=DF15R CRBN^(WT) extract preincubated with pomalidomide (30 μM).Representative immunoblot from two independent experiments with similarresults are shown.

FIGS. 25A-25F show that CRBN inducible-knockdown cells had a dose andtime dependent shRNA induction as measured by an increase in thepercentage of RFP positive cells. FIG. 25A: An inducible shRNA constructtargeting CRBN or a control construct was transduced into the multiplemyeloma cell lines H929 and U266. Inducible shRNA expression (marked byturbo-RFP) was monitored by flow cytometry over a period of 1 to 9 daysas indicated in the histograms (Top row). Annexin V assay stainingdemonstrated that following induction with doxycycline treatment, CRBNinducible-knockdown did not result in cell death (A Bottom row & C).FIG. 25B: CRBN protein expression was quantified by Western blotting.CRBN inducible-knockdown cells showed no significant changes in IRF4 oractin protein levels. FIG. 25C: Following doxycycline treatment, CRBNinducible-knockdown in H929 and U266 cells showed no effect in viabilityas measured by Annexin V+7AAD staining and analyzed by flow cytometryover a period of 1-9 days. FIGS. 25D-25F show that after 9 days of shRNAinducible knock-down, cells were treated with increasing doses ofpomalidomide and compound effect in cell viability was assayed by flowcytometry after 5 day treatment. In CRBN inducible knockdown cells,pomalidomide had reduced anti-proliferative effects compared toshControl knockdown cells. Data are shown as mean of three independentexperiments±s.d.

FIGS. 26A-26B show IL2 costimulation by pomalidomide. FIG. 26A:Co-stimulation of IL2 release by pomalidomide in human PBMCs treatedwith anti-CD3. Data are shown as mean±s.d. FIG. 26B: Costimulation ofIL2 release by anti-CD28 (squares) or pomalidomide (circles) in mousePBMC treated with anti-CD3. Data are shown as mean±s.d.

FIG. 27 shows V388 is essential for the degradation of IKZF1/3 bylenalidomide.

5. DETAILED DESCRIPTION

The compositions, methods and kits provided herein are based, in part,on the discovery that E3 ubiquitin ligases, including CRBN, undergoconformational changes or otherwise alter the surface, upon ligand(e.g., CMA) binding. As shown in FIG. 1, CRBN binds proteins, such asDDB1, Cul4 and Roc1 to form a E3-ubiquitan ligase complex, which serveto facilitate targeted protein ubiquitination and degradation. In thepresence of a CMA, the CRBN complex has an altered binding specificityand subsequent downstream biological effects. CRBN is believed to act asa novel substrate receptor for the complex. Without wishing to be boundby theory, it is believed that this ligand-dependent E3 ubiquitin ligase(e.g., CRBN) conformational change or alteration results in different E3ubiquitin ligase surfaces being exposed, thereby affecting therecruitment and engagement of different substrates to the E3 ubiquitinligase complex and resulting in the downstream differential phenotypicand/or therapeutic effects. In addition, ligands (including CMAs)provide binding interactions for the various different proteinsubstrates. In specific embodiments, the E3 ubiquitin ligase is CRBN,and the CRBN ligands include CMAs, such as CC-885, or any analogthereof.

5.1 Definitions

All patents, applications, published applications and other publicationsare incorporated by reference in their entirety. Unless definedotherwise, all technical and scientific terms used herein have the samemeaning as is commonly understood by one of ordinary skill in the art.All patents, applications, published applications and other publicationsare incorporated herein by reference in their entirety. In the eventthat there is a plurality of definitions for a term herein, those inthis section prevail unless stated otherwise.

The term “about” or “approximately” means within 20%, preferably within10%, and more preferably within 5% (or 1% or less) of a given value orrange.

As used herein, “administer” or “administration” refers to the act ofinjecting or otherwise physically delivering a substance as it existsoutside the body into a patient, such as by mucosal, intradermal,intravenous, intramuscular delivery and/or any other method of physicaldelivery described herein or known in the art. When a disease, disorderor condition, or a symptom thereof, is being treated, administration ofthe substance typically occurs after the onset of disease, disorder orcondition or symptoms thereof. When a disease, disorder or condition, orsymptoms thereof, are being prevented, administration of the substancetypically occurs before the onset of the disease, disorder or conditionor symptoms thereof.

“Biological sample” as used herein refers to a sample obtained from abiological subject, including sample of biological tissue or fluidorigin, obtained, reached, or collected in vivo or in situ. A biologicalsample also includes samples from a region of a biological subjectcontaining precancerous or cancer cells or tissues. Such samples can be,but are not limited to, organs, tissues, fractions and cells isolatedfrom a mammal. Exemplary biological samples include but are not limitedto cell lysate, a cell culture, a cell line, a tissue, oral tissue,gastrointestinal tissue, an organ, an organelle, a biological fluid, ablood sample, a urine sample, a skin sample, and the like. Preferredbiological samples include but are not limited to whole blood, partiallypurified blood, PBMCs, tissue biopsies, and the like.

A biological marker or “biomarker” is a substance whose detectionindicates a particular biological state, such as, for example, thepresence of cancer. In some embodiments, biomarkers can either bedetermined individually, or several biomarkers can be measuredsimultaneously. In some embodiments, a “biomarker” indicates a change inthe level of mRNA expression that may correlate with the risk orprogression of a disease, or with the susceptibility of the disease to agiven treatment. In some embodiments, the biomarker is a nucleic acid,such as a mRNA or cDNA. In additional embodiments, a “biomarker”indicates a change in the level of polypeptide or protein expressionthat may correlate with the risk, susceptibility to treatment, orprogression of a disease. In some embodiments, the biomarker can be apolypeptide or protein, or a fragment thereof. The relative level ofspecific proteins can be determined by methods known in the art. Forexample, antibody based methods, such as an immunoblot, enzyme-linkedimmunosorbent assay (ELISA), or other methods can be used.

The terms “cancer” and “cancerous” refer to or describe thephysiological condition in mammals that is typically characterized byunregulated cell growth. Examples of cancer include, but are not limitedto, blood-borne tumors (e.g., multiple myeloma, lymphoma and leukemia),and solid tumors. Other exemplary cancers are provided elsewhere herein.

The term “capture agent,” as used herein, refers to an agent that bindsan mRNA or protein through an interaction that is sufficient to permitthe agent to bind and concentrate the mRNA or protein from a homogeneousmixture.

The terms “cereblon” or “CRBN” and similar terms refers to thepolypeptides (“polypeptides,” “peptides” and “proteins” are usedinterchangeably herein) comprising the amino acid sequence any CRBN,such as a human CRBN protein (e.g., human CRBN isoform 1, GenBankAccession No. NP_057386; or human CRBN isoforms 2, GenBank Accession No.NP_001166953, each of which is herein incorporated by reference in itsentirety), and related polypeptides, including SNP variants thereof.Related CRBN polypeptides include allelic variants (e.g., SNP variants);splice variants; fragments; derivatives; substitution, deletion, andinsertion variants; fusion polypeptides; and interspecies homologs,which, in certain embodiments, retain CRBN activity and/or aresufficient to generate an anti-CRBN immune response.

As used herein, the term “cereblon-associated protein” or“CRBN-associated protein” refers to a protein that interacts with orbinds to CRBN directly or indirectly. In certain embodiments, a“cereblon-associated protein” or “CRBN-associated protein” is asubstrate of CRBN, for example, a protein substrate of the E3 ubiquitinligase complex involving CRBN, or the downstream substrates thereof. Inone embodiment, the CRBN-associated protein provided herein is asubstrate of CRBN such as IKZF3, also known as “Aiolos,” and/or IKZF1,also known as “Ikaros.” In certain embodiments, a “cereblon-associatedprotein” or “CRBN-associated protein” is a binding protein of CRBN.

As used herein and unless otherwise indicated, the term “co-crystal”means a crystalline form that contains more than one compound in acrystal lattice. Co-crystals include crystalline molecular complexes oftwo or more non-volatile compounds bound together in a crystal latticethrough non-ionic interactions. As used herein, co-crystals includepharmaceutical cocrystals wherein the crystalline molecular complexescontaining a therapeutic compound and one or more additionalnon-volatile compound(s) (referred to herein as counter-molecule(s)). Acounter-molecule in a pharmaceutical cocrystal is typically a non-toxicpharmaceutically acceptable molecule, such as, for example, foodadditives, preservatives, pharmaceutical excipients, or other APIs. Insome embodiments, pharmaceutical cocrystals enhance certainphysicochemical properties of drug products (e.g., solubility,dissolution rate, bioavailability and/or stability). withoutcompromising the chemical structural integrity of the activepharmaceutical ingredient (API). See, e.g., Jones et al.,“Pharmaceutical Cocrystals: An Emerging Approach to Physical PropertyEnhancement,” MRS Bulletin, 2006, 31, 875-879; Trask, “An Overview ofPharmaceutical Cocrystals as Intellectual Property,” MolecularPharmaceutics, 2007, 4(3), 301-309; Schultheiss & Newman,“Pharmaceutical Cocrystals and Their Physicochemical Properties,”Crystal Growth & Design, 2009, 9(6), 2950-2967; Shan & Zaworotko, “TheRole of Cocrystals in Pharmaceutical Science,” Drug Discovery Today,2008, 13(9/10), 440-446; and Vishweshwar et al., “PharmaceuticalCo-Crystals,” J. Pharm. Sci., 2006, 95(3), 499-516.

The term “complementary” refers to specific binding betweenpolynucleotides based on the sequences of the polynucleotides. As usedherein, a first polynucleotide and a second polynucleotide arecomplementary if they bind to each other in a hybridization assay understringent conditions, e.g. if they produce a given or detectable levelof signal in a hybridization assay. Portions of polynucleotides arecomplementary to each other if they follow conventional base-pairingrules, e.g. A pairs with T (or U) and G pairs with C, although smallregions (e.g. less than about 3 bases) of mismatch, insertion, ordeleted sequence may be present.

An improvement in the cancer or cancer-related disease can becharacterized as a complete or partial response. “Complete response”refers to an absence of clinically detectable disease with normalizationof any previously abnormal radiographic studies, bone marrow, andcerebrospinal fluid (CSF) or abnormal monoclonal protein measurements.“Partial response” refers to at least about a 10%, 20%, 30%, 40%, 50%,60%, 70%, 80%, or 90% decrease in all measurable tumor burden (i.e., thenumber of malignant cells present in the subject, or the measured bulkof tumor masses or the quantity of abnormal monoclonal protein) in theabsence of new lesions. The term “treatment” contemplates both acomplete and a partial response.

As used herein, the term “composition” is intended to encompass aproduct containing the specified ingredients (e.g., an antibody providedherein) and, optionally, in the specified amounts, as well as anyproduct which results, directly or indirectly, from combination of thespecified ingredients in, optionally, the specified amounts.

The term “cycle number” or “CT” when used herein in reference to PCRmethods, refers to the PCR cycle number at which the fluorescence levelpasses a given set threshold level. The CT measurement can be used, forexample, to approximate levels of mRNA in an original sample. The CTmeasurement is often used in terms of “dCT” or the “difference in theCT” score, when the CT of one nucleic acid is subtracted from the CT ofanother nucleic acid.

The terms “determining”, “measuring”, “evaluating”, “assessing” and“assaying” as used herein generally refer to any form of measurement,and include determining if an element is present or not. These termsinclude both quantitative and/or qualitative determinations. Assessingmay be relative or absolute. “Assessing the presence of” can includedetermining the amount of something present, as well as determiningwhether it is present or absent.

The term “effective amount” as used herein refers to the amount of atherapy (e.g., a composition provided herein) which is sufficient toreduce and/or ameliorate the severity and/or duration of a givendisease, disorder or condition and/or a symptom related thereto. Thisterm also encompasses an amount necessary for the reduction oramelioration of the advancement or progression of a given disease,disorder or condition, reduction or amelioration of the recurrence,development or onset of a given disease, disorder or condition, and/orto improve or enhance the prophylactic or therapeutic effect(s) ofanother therapy. In some embodiments, “effective amount” as used hereinalso refers to the amount of therapy provided herein to achieve aspecified result.

As used herein, an “effective patient tumor response” refers to anyincrease in the therapeutic benefit to the patient. An “effectivepatient tumor response” can be, for example, a 5%, 10%, 25%, 50%, or100% decrease in the rate of progress of the tumor. An “effectivepatient tumor response” can be, for example, a 5%, 10%, 25%, 50%, or100% decrease in the physical symptoms of a cancer. An “effectivepatient tumor response” can also be, for example, a 5%, 10%, 25%, 50%,100%, 200%, or more increase in the response of the patient, as measuredby any suitable means, such as gene expression, cell counts, assayresults, etc.

The term “expressed” or “expression” as used herein refers to thetranscription from a gene to give an RNA nucleic acid molecule at leastcomplementary in part to a region of one of the two nucleic acid strandsof the gene. The term “expressed” or “expression” as used herein alsorefers to the translation from the RNA molecule to give a protein, apolypeptide or a portion thereof.

As used herein, the term “immunomodulatory compound” or“immunomodulatory drug” refers generally to a molecule or agent capableof altering the immune response in some way. Non-limiting examples ofimmunomodulatory compounds include those disclosed in Section 5.8 below.

The terms “isolated” and “purified” refer to isolation of a substance(such as mRNA, antibody or protein) such that the substance comprises asubstantial portion of the sample in which it resides, i.e. greater thanthe substance is typically found in its natural or un-isolated state.Typically, a substantial portion of the sample comprises, e.g., greaterthan 1%, greater than 2%, greater than 5%, greater than 10%, greaterthan 20%, greater than 50%, or more, usually up to about 90%-100% of thesample. For example, a sample of isolated mRNA can typically comprise atleast about 1% total mRNA. Techniques for purifying polynucleotides arewell known in the art and include, for example, gel electrophoresis,ion-exchange chromatography, affinity chromatography, flow sorting, andsedimentation according to density.

A “label” or a “detectable moiety” in reference to a nucleic acid,refers to a composition that, when linked with a nucleic acid, rendersthe nucleic acid detectable, for example, by spectroscopic,photochemical, biochemical, immunochemical, or chemical means. Exemplarylabels include, but are not limited to, radioactive isotopes, magneticbeads, metallic beads, colloidal particles, fluorescent dyes, enzymes,biotin, digoxigenin, haptens, and the like. A “labeled nucleic acid oroligonucleotide probe” is generally one that is bound, eithercovalently, through a linker or a chemical bond, or noncovalently,through ionic bonds, van der Waals forces, electrostatic attractions,hydrophobic interactions, or hydrogen bonds, to a label such that thepresence of the nucleic acid or probe can be detected by detecting thepresence of the label bound to the nucleic acid or probe.

The term “likelihood” generally refers to an increase in the probabilityof an event. The term “likelihood” when used in reference to theeffectiveness of a patient tumor response generally contemplates anincreased probability that the rate of tumor progress or tumor cellgrowth will decrease. The term “likelihood” when used in reference tothe effectiveness of a patient tumor response can also generally meanthe increase of indicators, such as mRNA or protein expression, that mayevidence an increase in the progress in treating the tumor.

As used herein, the terms “manage,” “managing,” and “management” referto the beneficial effects that a subject derives from a therapy, whichdoes not result in a cure of the disease, disorder or condition. Incertain embodiments, a subject is administered one or more therapies to“manage” a disease, disorder or condition, or one or more symptomsthereof, so as to prevent the progression or worsening of the disease,disorder or condition.

The term “monitor,” as used herein, generally refers to the overseeing,supervision, regulation, watching, tracking, or surveillance of anactivity. For example, the term “monitoring the effectiveness of acompound” refers to tracking the effectiveness in treating a cancer in apatient or in a tumor cell culture. Similarly, the “monitoring,” whenused in connection with patient compliance, either individually, or in aclinical trial, refers to the tracking or confirming that the patient isactually taking a drug being tested as prescribed. The monitoring can beperformed, for example, by following the expression of mRNA or proteinbiomarkers.

The terms “nucleic acid” and “polynucleotide” are used interchangeablyherein to describe a polymer of any length composed of nucleotides,e.g., deoxyribonucleotides or ribonucleotides, or compounds producedsynthetically, which can hybridize with naturally occurring nucleicacids in a sequence specific manner analogous to that of two naturallyoccurring nucleic acids, e.g., can participate in Watson-Crick basepairing interactions. As used herein in the context of a polynucleotidesequence, the term “bases” (or “base”) is synonymous with “nucleotides”(or “nucleotide”), i.e., the monomer subunit of a polynucleotide. Theterms “nucleoside” and “nucleotide” are intended to include thosemoieties that contain not only the known purine and pyrimidine bases,but also other heterocyclic bases that have been modified. Suchmodifications include methylated purines or pyrimidines, acylatedpurines or pyrimidines, alkylated riboses or other heterocycles. Inaddition, the terms “nucleoside” and “nucleotide” include those moietiesthat contain not only conventional ribose and deoxyribose sugars, butother sugars as well. Modified nucleosides or nucleotides also includemodifications on the sugar moiety, e.g., wherein one or more of thehydroxyl groups are replaced with halogen atoms or aliphatic groups, orare functionalized as ethers, amines, or the like. “Analogues” refer tomolecules having structural features that are recognized in theliterature as being mimetics, derivatives, having analogous structures,or other like terms, and include, for example, polynucleotidesincorporating non-natural nucleotides, nucleotide mimetics such as2′-modified nucleosides, peptide nucleic acids, oligomeric nucleosidephosphonates, and any polynucleotide that has added substituent groups,such as protecting groups or linking moieties.

As used herein, the term “nucleotide,” nucleic acid,” “nucleic acidmolecule,” “polynucleotide,” and other similar terms are usedinterchangeable and include DNA, RNA, mRNA and the like.

The term “nucleic acid” or “oligonucleotide probe” refers to a nucleicacid capable of binding to a target nucleic acid of complementarysequence, such as the mRNA biomarkers provided herein, through one ormore types of chemical bonds, usually through complementary basepairing, usually through hydrogen bond formation. As used herein, aprobe may include natural (e.g., A, G, C, or T) or modified bases(7-deazaguanosine, inosine, etc.). In addition, the bases in a probe maybe joined by a linkage other than a phosphodiester bond, so long as itdoes not interfere with hybridization. It will be understood by one ofskill in the art that probes may bind target sequences lacking completecomplementarity with the probe sequence depending upon the stringency ofthe hybridization conditions. The probes are preferably directly labeledwith isotopes, for example, chromophores, lumiphores, chromogens, orindirectly labeled with biotin to which a streptavidin complex may laterbind. By assaying for the presence or absence of the probe, one candetect the presence or absence of a target mRNA biomarker of interest.

As used herein, and unless otherwise indicated, the term “opticallypure” means a composition that comprises one optical isomer of acompound and is substantially free of other isomers of that compound.For example, an optically pure composition of a compound having onechiral center will be substantially free of the opposite enantiomer ofthe compound. An optically pure composition of a compound having twochiral centers will be substantially free of other diastereomers of thecompound. A typical optically pure compound comprises greater than about80% by weight of one enantiomer of the compound and less than about 20%by weight of other enantiomers of the compound, more preferably greaterthan about 90% by weight of one enantiomer of the compound and less thanabout 10% by weight of the other enantiomers of the compound, even morepreferably greater than about 95% by weight of one enantiomer of thecompound and less than about 5% by weight of the other enantiomers ofthe compound, more preferably greater than about 97% by weight of oneenantiomer of the compound and less than about 3% by weight of the otherenantiomers of the compound, and most preferably greater than about 99%by weight of one enantiomer of the compound and less than about 1% byweight of the other enantiomers of the compound.

The terms “optional” or “optionally” as used herein means that thesubsequently described event or circumstance may or may not occur, andthat the description includes, without limitation, instances where saidevent or circumstance occurs and instances in which it does not.

The term “pharmaceutically acceptable” as used herein means beingapproved by a regulatory agency of the Federal or a state government, orlisted in the U.S. Pharmacopeia, European Pharmacopeia or othergenerally recognized Pharmacopeia for use in animals, and moreparticularly in humans.

As used herein and unless otherwise indicated, the term“pharmaceutically acceptable salt” encompasses non-toxic acid and baseaddition salts of the compound to which the term refers. Acceptablenon-toxic acid addition salts include those derived from organic andinorganic acids or bases know in the art, which include, for example,hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid,methanesulphonic acid, acetic acid, tartaric acid, lactic acid, succinicacid, citric acid, malic acid, maleic acid, sorbic acid, aconitic acid,salicylic acid, phthalic acid, embolic acid, enanthic acid, and thelike.

Compounds that are acidic in nature are capable of forming salts withvarious pharmaceutically acceptable bases. The bases that can be used toprepare pharmaceutically acceptable base addition salts of such acidiccompounds are those that form non-toxic base addition salts, i.e., saltscontaining pharmacologically acceptable cations such as, but not limitedto, alkali metal or alkaline earth metal salts and the calcium,magnesium, sodium or potassium salts in particular. Suitable organicbases include, but are not limited to, N,N-dibenzylethylenediamine,chloroprocaine, choline, diethanolamine, ethylenediamine, meglumaine(N-methylglucamine), lysine, and procaine.

The terms “polymerase chain reaction,” or “PCR,” as used hereingenerally refers to a procedure wherein small amounts of a nucleic acid,RNA and/or DNA, are amplified as described, for example, in U.S. Pat.No. 4,683,195 to Mullis. Generally, sequence information from the endsof the region of interest or beyond needs to be available, such thatoligonucleotide primers can be designed; these primers will be identicalor similar in sequence to opposite strands of the template to beamplified. The 5′ terminal nucleotides of the two primers may coincidewith the ends of the amplified material. PCR can be used to amplifyspecific RNA sequences, specific DNA sequences from total genomic DNA,and cDNA transcribed from total cellular RNA, bacteriophage or plasmidsequences, etc. See generally Mullis et al., Cold Spring Harbor Symp.Quant. Biol., 51: 263 (1987); Erlich, ed., PCR Technology, (StocktonPress, N Y, 1989).

As used herein the terms “polypeptide” and “protein” as usedinterchangeably herein, refer to a polymer of amino acids of three ormore amino acids in a serial array, linked through peptide bonds. Theterm “polypeptide” includes proteins, protein fragments, proteinanalogues, oligopeptides and the like. The term polypeptide as usedherein can also refer to a peptide. The amino acids making up thepolypeptide may be naturally derived, or may be synthetic. Thepolypeptide can be purified from a biological sample.

The term “predict” generally means to determine or tell in advance. Whenused to “predict” the effectiveness of a cancer treatment, for example,the term “predict” can mean that the likelihood of the outcome of thecancer treatment can be determined at the outset, before the treatmenthas begun, or before the treatment period has progressed substantially.

As used herein, the term “prophylactic agent” refers to any agent thatcan totally or partially inhibit the development, recurrence, onset orspread of a disease, disorder or condition and/or symptom relatedthereto in a subject. In certain embodiments, the term “prophylacticagent” refers to a compound provided herein. In certain otherembodiments, the term “prophylactic agent” refers to an agent other thana compound provided herein. In certain embodiments, a prophylactic agentis an agent which is known to be useful to or has been or is currentlybeing used to prevent a disease, disorder or condition and/or a symptomrelated thereto or impede the onset, development, progression and/orseverity of a disease, disorder or condition and/or a symptom relatedthereto.

The term “probe” as used herein, refers to a capture agent that isdirected to a specific target mRNA biomarker sequence. Accordingly, eachprobe of a probe set has a respective target mRNA biomarker. Aprobe/target mRNA duplex is a structure formed by hybridizing a probe toits target mRNA biomarker.

The term “refractory or resistant” refers to a circumstance wherepatients, even after intensive treatment, have residual cancer cells(e.g., leukemia or lymphoma cells) in their lymphatic system, bloodand/or blood forming tissues (e.g., marrow).

The term “regulate” as used herein refers to controlling the activity ofa molecule or biological function, such as enhancing or diminishing theactivity or function.

The term “sample” as used herein relates to a material or mixture ofmaterials, typically, although not necessarily, in fluid form,containing one or more components of interest.

The term “sensitivity” and “sensitive” when made in reference totreatment with compound is a relative term which refers to the degree ofeffectiveness of the compound in lessening or decreasing the progress ofa tumor or the disease being treated. For example, the term “increasedsensitivity” when used in reference to treatment of a cell or tumor inconnection with a compound refers to an increase of, at least a 5%, ormore, in the effectiveness of the tumor treatment.

“Sequence identity” or “identity” in the context of two nucleic acidsequences refers to the residues in the two sequences which are the samewhen aligned for maximum correspondence over a specified comparisonwindow, and can take into consideration additions, deletions andsubstitutions.

As used herein and unless otherwise indicated, the term “solvate” meansa compound provided herein or a salt thereof, that further includes astoichiometric or non-stoichiometric amount of solvent bound bynon-covalent intermolecular forces. Where the solvent is water, thesolvate is a hydrate.

As used herein and unless otherwise indicated, the term “stereomericallypure” means a composition that comprises one stereoisomer of a compoundand is substantially free of other stereoisomers of that compound. Forexample, a stereomerically pure composition of a compound having onechiral center will be substantially free of the opposite enantiomer ofthe compound. A stereomerically pure composition of a compound havingtwo chiral centers will be substantially free of other diastereomers ofthe compound. A typical stereomerically pure compound comprises greaterthan about 80% by weight of one stereoisomer of the compound and lessthan about 20% by weight of other stereoisomers of the compound, morepreferably greater than about 90% by weight of one stereoisomer of thecompound and less than about 10% by weight of the other stereoisomers ofthe compound, even more preferably greater than about 95% by weight ofone stereoisomer of the compound and less than about 5% by weight of theother stereoisomers of the compound, and most preferably greater thanabout 97% by weight of one stereoisomer of the compound and less thanabout 3% by weight of the other stereoisomers of the compound. As usedherein and unless otherwise indicated, the term “stereomericallyenriched” means a composition that comprises greater than about 60% byweight of one stereoisomer of a compound, preferably greater than about70% by weight, more preferably greater than about 80% by weight of onestereoisomer of a compound. As used herein and unless otherwiseindicated, the term “enantiomerically pure” means a stereomerically purecomposition of a compound having one chiral center. Similarly, the term“stereomerically enriched” means a stereomerically enriched compositionof a compound having one chiral center.

The term “stringent assay conditions” refers to conditions that arecompatible to produce binding pairs of nucleic acids, e.g., probes andtarget mRNAs, of sufficient complementarity to provide for the desiredlevel of specificity in the assay while being generally incompatible tothe formation of binding pairs between binding members of insufficientcomplementarity to provide for the desired specificity. The termstringent assay conditions generally refers to the combination ofhybridization and wash conditions.

As used herein, the terms “subject” and “patient” are usedinterchangeably. As used herein, a subject can be a mammal such as anon-primate (e.g., cows, pigs, horses, cats, dogs, rats, etc.) or aprimate (e.g., monkey and human). In specific embodiments, the subjectis a human. In one embodiment, the subject is a mammal (e.g., a human)having a disease, disorder or condition. In another embodiment, thesubject is a mammal (e.g., a human) at risk of developing a disease,disorder or condition.

The term “substantial identity” or “homologous” in their variousgrammatical forms in the context of polynucleotides generally means thata polynucleotide comprises a sequence that has a desired identity, forexample, at least 60% identity, preferably at least 70% sequenceidentity, more preferably at least 80%, still more preferably at least90% and even more preferably at least 95%, compared to a referencesequence. Another indication that nucleotide sequences are substantiallyidentical is if two molecules hybridize to each other under stringentconditions.

As used herein, and unless otherwise specified, the term“therapeutically effective amount” of a compound is an amount sufficientto provide a therapeutic benefit in the treatment or management of acancer, or to delay or minimize one or more symptoms associated with thepresence of the cancer. A therapeutically effective amount of a compoundmeans an amount of therapeutic agent, alone or in combination with othertherapies, which provides a therapeutic benefit in the treatment ormanagement of the cancer. The term “therapeutically effective amount”can encompass an amount that improves overall therapy, reduces or avoidssymptoms or causes of cancer, or enhances the therapeutic efficacy ofanother therapeutic agent.

As used herein, the term “therapy” refers to any protocol, method and/oragent that can be used in the prevention, management, treatment and/oramelioration of a given disease, disorder or condition. In certainembodiments, the terms “therapies” and “therapy” refer to a drugtherapy, biological therapy, supportive therapy, and/or other therapiesuseful in the prevention, management, treatment and/or amelioration of agiven disease, disorder or condition known to one of skill in the artsuch as medical personnel.

As used herein, and unless otherwise specified, the terms “treat,”“treating” and “treatment” refer to an action that occurs while apatient is suffering from the specified disease, disorder or condition.As used herein, the terms “treat,” “treatment” and “treating” refer tothe reduction or amelioration of the progression, severity, and/orduration of a disease, disorder or condition resulting from theadministration of one or more therapies.

“Tumor,” as used herein, refers to all neoplastic cell growth andproliferation, whether malignant or benign, and all pre-cancerous andcancerous cells and tissues. “Neoplastic,” as used herein, refers to anyform of dysregulated or unregulated cell growth, whether malignant orbenign, resulting in abnormal tissue growth. Thus, “neoplastic cells”include malignant and benign cells having dysregulated or unregulatedcell growth.

An mRNA that is “upregulated” is generally increased upon a giventreatment or condition. An mRNA that is “downregulated” generally refersto a decrease in the level of expression of the mRNA in response to agiven treatment or condition. In some situations, the mRNA level canremain unchanged upon a given treatment or condition. An mRNA from apatient sample can be “upregulated” when treated with a drug, ascompared to a non-treated control. This upregulation can be, forexample, an increase of about 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%,90%, 100%, 200%, 300%, 500%, 1,000%, 5,000% or more of the comparativecontrol mRNA level. Alternatively, an mRNA can be “downregulated”, orexpressed at a lower level, in response to administration of certaincompounds or other agents. A downregulated mRNA can be, for example,present at a level of about 99%, 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%,20%, 10%, 1% or less of the comparative control mRNA level. Similarly,the level of a polypeptide or protein biomarker from a patient samplecan be increased when treated with a drug, as compared to a non-treatedcontrol. This increase can be about 5%, 10%, 20%, 30%, 40%, 50%, 60%,70%, 90%, 100%, 200%, 300%, 500%, 1,000%, 5,000% or more of thecomparative control protein level. Alternatively, the level of a proteinbiomarker can be decreased in response to administration of certaincompounds or other agents. This decrease can be, for example, present ata level of about 99%, 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%,1% or less of the comparative control protein level.

It should be noted that if there is a discrepancy between a depictedstructure and a name given that structure, the depicted structure is tobe accorded more weight. In addition, if the stereochemistry of astructure or a portion of a structure is not indicated with, forexample, bold or dashed lines, the structure or portion of the structureis to be interpreted as encompassing all stereoisomers of it.

The practice of the embodiments provided herein will employ, unlessotherwise indicated, conventional techniques of molecular biology,microbiology, and immunology, which are within the skill of thoseworking in the art. Such techniques are explained fully in theliterature. Examples of particularly suitable texts for consultationinclude the following: Sambrook et al. (1989) Molecular Cloning; ALaboratory Manual (2d ed.); D. N Glover, ed. (1985) DNA Cloning, VolumesI and II; M. J. Gait, ed. (1984) Oligonucleotide Synthesis; B. D. Hames& S J. Higgins, eds. (1984) Nucleic Acid Hybridization; B. D. Hames & S.J. Higgins, eds. (1984) Transcription and Translation; R. I. Freshney,ed. (1986) Animal Cell Culture; Immobilized Cells and Enzymes (IRLPress, 1986); Immunochemical Methods in Cell and Molecular Biology(Academic Press, London); Scopes (1987) Protein Purification: Principlesand Practice (2d ed.; Springer Verlag, N.Y.); and D. M. Weir and C. C.Blackwell, eds. (1986) Handbook of Experimental Immunology, VolumesI-IV.

5.2 Methods of Identifying Compounds

Provided herein, for example, are compositions, methods and kits forscreening or otherwise identifying a compound, that binds to an E3ubiquitin ligase. In certain embodiments, the compound induces aconformational change in the E3 ubiquitin ligase ligand binding pocket.In other embodiments, the compound alters the properties of the E3ubiquitin ligase surface. In some embodiments of the variouscompositions and methods provided herein, the compound alters the E3ubiquitin ligase surface adjacent to the E3 ubiquitin ligase ligandbinding pocket. In other embodiments, the compound alters one or moresurrounding loops or other surface of the E3 ubiquitin ligase ligandbinding pocket. In certain embodiments, the properties of the E3ubiquitin ligase surface are altered by the placement of compoundappendages. In a specific embodiment, the compound is a CMA. In anotherspecific embodiment, the E3 ubiquitin ligase is CRBN.

While exemplary methods provided below and elsewhere refer to CRBNconformational changes (e.g., within the CMA binding pocket) or otheralterations in the properties of a CRBN surface (e.g., on an adjacentregion of the protein, such as a region adjacent to the CMA-bindingpocket), it is understood that CRBN is merely illustrative and that themethods provided herein can be utilized with other E3 ubiquitin ligases.

In one aspect, provided herein is a method of identifying a testcompound that induces a CRBN conformational change (e.g., within theCMA-binding pocket of the CRBN) or otherwise altering the properties ofa CRBN surface (e.g., on an adjacent region of the protein). In certainembodiments, the method comprises (a) (i) obtaining a first crystalstructure of CRBN and a reference compound, and (ii) determining athree-dimensional structure of the first crystal by x-ray diffraction toobtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofa compound that induces a CRBN conformational change or alteration. Insome embodiments, a CRBN conformational change is induced. In otherembodiments, an alteration of the properties of a CRBN surface areinduced. In some embodiments, the first set of atomic coordinates and/orsaid second set of atomic coordinates define a CMA binding domain. Incertain embodiments, the difference in atomic coordinates is determinedby assessing differences in atomic distances. Also provided herein is atest compound identified by this method. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN.

In another aspect, provided herein is a method of identifying a testcompound that induces a CRBN conformational change (e.g., within theCMA-binding pocket of the CRBN) or otherwise alters the properties of aCRBN surface (e.g., on an adjacent region of the protein). In certainembodiments, the method comprises (a) (i) obtaining a firstthree-dimensional structure of CRBN and a reference compound; (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. Alsoprovided herein is a test compound identified by this method. In someembodiments, a CRBN conformational change is induced. In otherembodiments, an alteration of the properties of a CRBN surface areinduced. In certain embodiments, the conformational change or alterationoccurs in a CMA binding pocket of the CRBN. In some embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on W380, W386 and/or W400 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on E377 of CRBN. In other embodiments, the conformational changeor alteration in said CMA binding pocket has an effect on V388 of CRBN.In an embodiment, the conformational change or alteration is assessed byx-ray crystallography. In another embodiment, the conformational changeor alteration is assessed by a method comprising (a) (i) obtaining afirst crystal structure of CRBN and a reference compound, and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change or alteration is assessed by a method comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound that induces aCRBN conformational change or alteration. In some embodiments, the firstand/or second three-dimensional structures include a CMA binding domainof the CRBN. In other embodiments, the three-dimensional structure isassessed using x-ray crystallography, NMR spectroscopy, dualpolarization interferometry, vibrational spectroscopy, or cryo-elecronmicroscopy. In some embodiments, the CRBN is further bound to DDB1,Cul4, Roc1, or any combination thereof.

In another aspect, provided herein is a method of identifying a testcompound that has a specific downstream biological activity comprising:(a) (i) obtaining a first crystal structure of CRBN and a referencecompound, and (ii) determining a three-dimensional structure of thefirst crystal by x-ray diffraction to obtain a first set of atomiccoordinates; (b) (i) obtaining a second crystal comprising CRBN and thetest compound, and (ii) determining a three-dimensional structure of thesecond crystal by x-ray diffraction to obtain a second set of atomiccoordinates; and (c) comparing said first set of atomic coordinates withsaid second set of atomic coordinates; wherein a difference in atomiccoordinates is indicative of a compound has the specific downstreambiological activity. In some embodiments, the first set of atomiccoordinates and/or said second set of atomic coordinates define a CMAbinding domain. In certain embodiments, the difference in atomiccoordinates is determined by assessing differences in atomic distances.In some embodiments, the method further comprises assaying the specificbiological activity. Also provided herein is a test compound identifiedby this method. In certain embodiments, the method further comprisesadministering said compound to a patient, wherein said biologicalactivity is modulated in said patient. In certain embodiments, thepatient has a disease, and wherein one or more symptoms of said diseaseare alleviated following said administration. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN. In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN.

In another aspect, provided herein is a method of identifying a testcompound that has a specific downstream biological activity comprising(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound has thespecific downstream biological activity. Also provided herein is a testcompound identified by this method. In some embodiments, the testcompound induces a CRBN conformational change. In other embodiments, thetest compound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In some embodiments, the biological activity is a tumoricidal effect. Inother embodiments, the biological activity is an apoptosis effect. Insome embodiments, the biological activity is anti-proliferation. In yetother embodiments, the biological activity is PBMC viability. In someembodiments, the biological activity is toxicity. In certainembodiments, the biological activity is substrate degradation. In oneembodiments, the biological activity is Aiolos degradation. In anotherembodiments, the biological activity is Ikaros degradation. In otherembodiments, the biological activity is an immune-mediated effect. Inanother embodiment, the biological activity is IL-2 induction. In someembodiments, the biological activity is IL-2 repression. In yet otherembodiments, the biological activity is a HbF effect. Any combination ofone, two, three or more of the aforementioned biological activities isalso contemplated. In certain embodiments, the biological activity isbased on specific cell type categories. In other embodiments, thebiological activity is based on specific tissue type categories. In yetother embodiments, the biological activity is based on solid tumors orsolid tumor categories. In some embodiments, the biological activity isbased on non-solid tumor categories.

In another aspect, provided herein is a method of identifying a testcompound that has a specific therapeutic efficacy comprising: (a) (i)obtaining a first crystal structure of CRBN and a reference compound,and (ii) determining a three-dimensional structure of the first crystalby x-ray diffraction to obtain a first set of atomic coordinates; (b)(i) obtaining a second crystal comprising CRBN and the test compound,and (ii) determining a three-dimensional structure of the second crystalby x-ray diffraction to obtain a second set of atomic coordinates; and(c) comparing said first set of atomic coordinates with said second setof atomic coordinates; wherein a difference in atomic coordinates isindicative of a compound has the specific therapeutic efficacy. In someembodiments, the first set of atomic coordinates and/or said second setof atomic coordinates define a CMA binding domain. In certainembodiments, the difference in atomic coordinates is determined byassessing differences in atomic distances. Also provided herein is atest compound identified by this method. In certain embodiments, themethod further comprises administering said compound to a patient havingdisease, disorder or condition, wherein one or more symptoms of saiddisease, disorder or condition is alleviated following saidadministration. In certain embodiments, the conformational change oralteration occurs in a CMA binding pocket of the CRBN. In someembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on W380, W386 and/or W400 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on E377 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on V388 of CRBN.

In another aspect, provided herein is a method of identifying a testcompound that has a specific downstream therapeutic efficacy comprising:(a) (i) obtaining a first three-dimensional structure of CRBN and areference compound; (b) (i) obtaining a second three-dimensionalstructure of CRBN and the test compound; and (c) comparing said firstthree-dimensional structure with said second three-dimensionalstructure; wherein a difference in the first and secondthree-dimensional structures is indicative of a compound has thespecific downstream biological activity. Also provided herein is a testcompound identified by this method. In some embodiments, the testcompound induces a CRBN conformational change. In other embodiments, thetest compound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

5.2.1. Computer-Based Design of Compounds

Provided herein are methods of designing compounds based on fit withinthe CMA binding pocket of CRBN. In some embodiments, the methods arecomputer-based methods.

In one aspect, provided herein is a method of designing a test compoundbased on fit within CMA binding pocket of CRBN, comprising: (a)generating on a computer, three-dimensional structural features of aCRBN having a conformational change or alteration in the CMA bindingpocket, (b) designing a test compound capable of selectively binding tosaid CMA binding pocket, (c) synthesizing said test compound, (d)contacting CRBN with said synthesized test compound, and (e) determiningif said test compound binds to said CRBN. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN.

In one embodiment, the method comprises (i) generating (e.g., on acomputer) a three-dimensional structural features of a CRBN having aconformational change or alteration in the CMA binding pocket, (ii)designing a compound capable of selectively binding to said CMA bindingpocket, (iii) synthesizing said compound, (iv) contacting a CRBN withsaid synthesized compound, and (v) identifying a synthesized compoundthat binds to said CMA binding pocket. In certain embodiments, the CMAbinding pocket conformational change or alteration of the CRBN isdefined by atomic coordinates as set forth in any one of Tables 3, 4, 5,6 or 7; or a three dimensional structure as set forth in any one ofFIGS. 12-18 or 20. In some embodiments, the CMA binding pocket comprisesW380, W386 and/or W400. Exemplary CMA binding pockets are provided inFIGS. 12-20 and 22A-22C; and Tables 3-5. In some embodiments, the methodfurther comprises methods provided in Example 6.9.3.

In certain embodiments, the test compounds are synthesized and assayedfor a biological activity as provided elsewhere herein. For example, insome embodiments, the biological activity is a tumoricidal effect,apoptosis effect, anti-proliferation, increased proliferation, PBMCviability, toxicity, substrate degradation (e.g., Aiolos or Ikarosdegradation), an immune-mediated effect, IL-2 induction, or IL-2repression.

In other embodiments, the test compounds are synthesized and assayed fora therapeutic activity as provided elsewhere herein.

5.3 Crystalline CRBN

Provided herein are crystalline forms of CRBN, for example, unbound CRBNor CRBN complexed with a CMA. In one embodiment, the crystalline formhas atomic coordinates as set forth in any one of Tables 3, 4, 5, 6 or7. In some embodiments, the crystalline form has a three dimensionalstructure as set forth in any one of FIGS. 12-18 or 20. In certainembodiments, the CRBN is complexed with (or otherwise bound to) DDB1. Inother embodiments, the CRBN is complexed with (or otherwise bound to) aCMA. In certain embodiments, the CMA is thalidomide, pomalidomide orlenalidomide. In other embodiments, the CRBN is complexed with (orotherwise bound to) DDB and a CMA. Exemplary crystals and methods ofmaking the crystals are provided in Example 6.9.3 below.

5.3.1. Crystalline CRBN—Unbound

Provided herein is a crystalline CRBN. In certain embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof.

In one embodiment, the CRBN has a three-dimensional structure. Incertain embodiments, the three-dimensional structure is determined byx-ray diffraction. In a specific embodiment, the three-dimensionalstructure has the following atomic coordinates In one embodiment, thecrystalline form has atomic coordinates as set forth in any one ofTables 3, 4, 5, 6 or 7. In some embodiments, the crystalline form has athree dimensional structure as set forth in any one of FIGS. 12-18 or20. In certain embodiments, the CRBN is complexed with (or otherwisebound to) DDB1. In other embodiments, the CRBN is complexed with (orotherwise bound to) a CMA. In certain embodiments, the CMA isthalidomide, pomalidomide or lenalidomide. In other embodiments, theCRBN is complexed with (or otherwise bound to) DDB and a CMA. Exemplarycrystals and methods of making the crystals are provided in Example6.9.3 below.

In a specific embodiment, the crystalline form has atomic coordinatesset forth in Table 4. In other embodiments, the crystalline form hasatomic coordinates set forth in Table 5. In other embodiments, thecrystalline form has atomic coordinates set forth in Table 6. In otherembodiments, the crystalline form has atomic coordinates set forth inTable 7.

In some embodiments, the crystalline form comprises a fragment of CRBN.In other embodiments, the crystalline form comprises a fragment of CRBN,either alone or in combination with DDB1 and/or a CMA provided herein.

Also provided herein is a method to obtain a crystalline CRBN, whereinsaid method comprises concentrating the CRBN and obtaining a crystalusing methods provided in Example 6.9.3 below.

5.3.2. Crystalline CRBN—Bound

Provided herein is a crystal of a complex comprising CRBN and a CMA. Inone embodiment, the CMA is an immunomodulatory compound provided herein(see, e.g., Section 5.8 below). In other embodiments, the CMA is CC-885or an analog thereof. In certain embodiments, the CRBN is further boundto DDB1, Cul4, Roc1, or any combination thereof.

In one embodiment, the crystal of the complex has a three-dimensionalstructure. In certain embodiments, the three-dimensional structure isdetermined by x-ray diffraction. In one embodiment, the crystal hasatomic coordinates as set forth in any one of Tables 3, 4, 5, 6 or 7. Insome embodiments, the crystal has a three dimensional structure as setforth in any one of FIGS. 12-18 or 20. In certain embodiments, the CRBNis complexed with (or otherwise bound to) DDB1. In other embodiments,the CRBN is complexed with (or otherwise bound to) a CMA. In certainembodiments, the CMA is thalidomide, pomalidomide or lenalidomide. Inother embodiments, the CRBN is complexed with (or otherwise bound to)DDB and a CMA. Exemplary crystals and methods of making the crystals areprovided in Example 6.9.3 below.

In one embodiment, the crystal has atomic coordinates set forth in Table3. In a specific embodiment, the crystal has atomic coordinates setforth in Table 4. In other embodiments, the crystal has atomiccoordinates set forth in Table 5. In other embodiments, the crystal hasatomic coordinates set forth in Table 6. In other embodiments, thecrystal has atomic coordinates set forth in Table 7.

Generally speaking, those of skill in the art will understand that theterm “coordinates” or “structure coordinates” refers to Cartesiancoordinates derived from mathematical equations related to the patternsobtained on diffraction of a monochromatic beam of X-rays by the atoms(scattering centers) of a polypeptide in crystal form. The diffractiondata are used to calculate an electron density map of the repeating unitof the crystal. The electron density maps are then used to estimate thepositions of the individual atoms of the polypeptide to construct apolypeptide model. Those of skill in the art will also understand that aset of structure coordinates for a polypeptide model is a relative setof points that define a structure in three dimensions.

Those of skill in the art understand that a set of structure coordinatesdetermined by X-ray crystallography is approximate and not withoutstandard error. Due to inherent limitations of the resolution ofdiffraction data, the positions of individual atoms in a polypeptidemodel are necessarily approximate. Slight variations in atomic positionwithin a polypeptide model will have little effect on overall shape andstructure of the polypeptide model. If such variations are within anacceptable standard error as compared to the original coordinates, theresulting three-dimensional shape and structure is considered to bestructurally equivalent. By way of example, those skilled in the artunderstand that a set of structure coordinates for a given polypeptidemodel having a root mean square deviation of non-hydrogen atoms of lessthan about 1.5 Å when superimposed on the non-hydrogen atom positions ofa second set of structure coordinates for a second polypeptide model aretypically considered to be substantially identical or homologous.

It also is possible that an entirely different set of coordinates coulddefine a similar or identical shape. Slight variations in structurecoordinates also can be generated by mathematically manipulating thecoordinates of a polypeptide model. For example, the structurecoordinates set forth herein could be manipulated by crystallographicpermutations of the structure coordinates, fractionalization of thestructure coordinates, integer additions or subtractions to sets of thestructure coordinates, inversion of the structure coordinates, or anycombination thereof. Alternatively, modification in the crystalstructure due to mutations, additions, substitutions, and/or deletionsof amino acids, or other changes in any of the components that make upthe crystal, could also account for variations in structure coordinates.If such variations are within an acceptable standard error as comparedto the original coordinates, the resulting three-dimensional shape isconsidered to be the same as that of the unmodified crystal structure.

In some embodiments, the crystal comprises a fragment of CRBN. In otherembodiments, the crystal comprises a fragment of CRBN, either alone orin combination with DDB1 and/or a CMA provided herein.

In certain embodiments, the three-dimensional structure is indicative ofa conformational change or alteration in the CRBN. In some embodiments,the CRBN conformational change or alteration is as compared to anunbound CRBN. In other embodiments, the CRBN conformational change oralteration is as compared to complex comprising the CRBN and an analogof the CMA. In yet other embodiments, the CRBN conformational change oralteration is as compared to a complex comprising CRBN and a differentCMA.

Also provided herein is a crystal of a complex comprising CRBN and aCMA, or an analog thereof. Also provided herein is a method of obtainingthe crystal, comprising concentrating a purified complex of the CRBN andthe CMA, or analog thereof, and obtaining the crystal. In certainembodiments, the method further comprises methods provided in Example6.9.3 below.

Also provided herein is a crystal of a complex comprising CRBN and acompound, wherein said crystal has a three-dimensional structure asdetermined by x-ray diffraction having the following atomic coordinatesIn one embodiment, the crystal has atomic coordinates as set forth inany one of Tables 3, 4, 5, 6 or 7. In some embodiments, the crystal hasa three dimensional structure as set forth in any one of FIGS. 12-18 or20. In certain embodiments, the CRBN is complexed with (or otherwisebound to) DDB1. In other embodiments, the CRBN is complexed with (orotherwise bound to) a CMA. In certain embodiments, the CMA isthalidomide, pomalidomide or lenalidomide. In other embodiments, theCRBN is complexed with (or otherwise bound to) DDB and a CMA. Exemplarycrystals and methods of making the crystals are provided in Example6.9.3 below.

In one embodiment, the crystal has atomic coordinates set forth in Table3. In a specific embodiment, the crystal has atomic coordinates setforth in Table 4. In other embodiments, the crystal has atomiccoordinates set forth in Table 5. In other embodiments, the crystal hasatomic coordinates set forth in Table 6. In other embodiments, thecrystal has atomic coordinates set forth in Table 7.

In some embodiments, the crystal comprises a fragment of CRBN. In otherembodiments, the crystal comprises a fragment of CRBN, either alone orin combination with DDB1 and/or a CMA provided herein.

Also provided herein is a crystal of a complex comprising a CRBN and acompound, wherein said crystal has a three-dimensional structure asdetermined by x-ray diffraction, wherein said three-dimensionalstructure has atomic coordinates as set forth in any one of Tables 3, 4,5, 6 or 7 indicative of CRBN conformational change or alteration. Insome embodiments, the CRBN conformational change or alteration is ascompared to a complex comprising CRBN and reference compound. In certainembodiments, the conformational change or alteration occurs in a CMAbinding pocket of the CRBN. In some embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on W380,W386 and/or W400 of CRBN. In other embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on E377 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on V388 of CRBN.

In certain embodiments of the various compositions and methods providedherein, the CRBN is bound to DDB1. In some embodiments, the CRBN isbound to Cul4. In other embodiments, the CRBN is bound to Roc1. In someembodiments, the CRBN is bound to DDB1 and Cul4. In other embodiments,the CRBN is bound to DDB1 and Roc1. In yet other embodiments, the CRBNis bound to Cul4 and Roc1. In some embodiments, the CRBN is bound toDDB1, Cul4 and Roc1. In certain embodiments, CRBN that is bound to DDB1,Cul4 and/or Roc1 is a complex with DDB1, Cul4 and/or Roc1, respectively.

In some embodiments of the various compositions and methods providedherein, the CMA is an immunomodulatory compound provided herein (see,e.g., Section 5.8 below). In certain embodiments, the CMA isthalidomide. In other embodiments, the CMA is pomalidomide. In someembodiments, the CMA is CC-220. In other embodiments, the CMA is CC-885.In certain embodiments, the CMA is a thalidomide analog. In otherembodiments, the CMA is a pomalidomide analog. In some embodiments, theCMA is a CC-220 analog. In other embodiments, the CMA is a CC-885analog. In other embodiments, the CMA is not thalidomide. In otherembodiments, the CMA is not pomalidomide. In some embodiments, the CMAis not CC-220. In other embodiments, the CMA is not CC-885. In otherembodiments, the CMA is not a thalidomide analog. In other embodiments,the CMA is not a pomalidomide analog. In some embodiments, the CMA isnot a CC-220 analog. In other embodiments, the CMA is not a CC-885analog.

Also provided herein are methods of identifying a compound that inducesa CRBN conformational change (e.g., within the CMA-binding pocket of theCRBN) or otherwise alters the properties of a CRBN surface (e.g., on anadjacent region of the protein) comprising: (i) obtaining a crystalcomprising a complex comprising the CRBN and the compound, (ii)determining the three-dimensional structure of the crystal by x-raydiffraction to obtain atomic coordinates, and (iii) comparing saidatomic coordinates with atomic coordinates provided in any one of Tables3, 4, 5, 6 or 7, wherein a change or shift in atomic coordinates isindicative of a compound that induces said CRBN conformational change oralteration. In certain embodiments, the atomic coordinates define theCMA binding domain. Also provided herein are compounds identified bythese methods. In some embodiments, the test compound induces a CRBNconformational change or alteration. In other embodiments, the testcompound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein.

5.4 Methods of Inducing a CRBN Conformational Change or Alteration

Provided herein are methods of inducing a CRBN conformational change(e.g., within the CMA-binding pocket of the CRBN) or otherwise altersthe properties of a CRBN surface (e.g., on an adjacent region of theprotein), said method comprising contacting the CRBN with a CMA.

In certain embodiments, a conformational change in the CMA-bindingpocket is induced. In other embodiments, an alteration in the propertiesof the CRBN surface is induced. In some embodiments, a CRBN surfaceadjacent to the CMA-binding pocket is altered. In other embodiments, oneor more surrounding loops that are adjacent or otherwise surround theCMA binding pocket are altered. In certain embodiments, the propertiesof the CRBN surface are altered by the placement of a compound'sappendages. In a specific embodiment, the compound is a CMA.

In some embodiments, the CRBN conformational change results in analtered substrate specificity, biological activity and/or therapeuticutility as compared to CRBN in the absence of the CMA. In someembodiments, the CRBN conformational change results in an alteredsubstrate specificity, biological activity and/or therapeutic utility ascompared to CRBN in the presence of a different CMA. In someembodiments, a CRBN conformational change is induced. In otherembodiments, an alteration of the properties of a CRBN surface areinduced.

Provided herein, in certain embodiments, is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or otherwise alters the properties of a CRBN surface (e.g., on anadjacent region of the protein), comprising contacting the CRBN with atest compound, wherein said CRBN conformational change or alterationcomprises a conformational change or alteration within the CMA bindingpocket of the CRBN that is different than the conformational change oralteration within the CMA binding pocket of a CRBN contacted with areference compound. In some embodiments, the CRBN conformational changeor alteration results in a different biological activity. In someembodiments, the CRBN conformational change or alteration results in adifferent therapeutic utility. In other embodiments, the CRBNconformational change or alteration results in a different substratespecificity. In some embodiments, the test compound induces a CRBNconformational change or alteration. In other embodiments, the testcompound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

Also provided herein is a composition comprising a CRBN and a testcompound, wherein said CRBN has a conformational change or alteration ascompared to a reference compound. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

Also provided herein is a compound that induces a CRBN conformationalchange (e.g., within the CMA-binding pocket of the CRBN) or otherwisealters the properties of a CRBN surface (e.g., on an adjacent region ofthe protein) upon contact with said CRBN, as compared to theconformational change or alteration as compared to a reference compound.In some embodiments, the CRBN conformational change or alterationresults in a different biological activity. In some embodiments, theCRBN conformational change or alteration results in a differenttherapeutic utility. In other embodiments, the CRBN conformationalchange or alteration results in a different substrate specificity. Insome embodiments, the compound induces a CRBN conformational change oralteration. In other embodiments, the compound alters the properties ofthe CRBN surface. In certain embodiments, the properties of the CRBNsurface are altered by the placement of compound appendages. In certainembodiments, the conformational change or alteration occurs in a CMAbinding pocket of the CRBN. In some embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on W380,W386 and/or W400 of CRBN. In other embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on E377 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on V388 of CRBN. In certainembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on an adjacent region of the protein. In anembodiment, the conformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

Also provided herein is a complex comprising a CRBN and test compound,wherein said CRBN has a conformational change or alteration as comparedto a conformational change or alteration of said CRBN contacted with areference compound. I In some embodiments, the CRBN has a conformationalchange or alteration. In other embodiments, the CRBN has an alterationof the properties of the CRBN surface. n certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In various embodiments of the methods provided herein, the compound is acompound provided herein (see, e.g., Section 5.8 below). In otherembodiments, the compound is not a compound provided herein. In variousembodiments of the methods provided herein, the compound is a CMA. Incertain embodiments, the CMA is thalidomide, lenalidomide, pomalidomide,3-(5-amino-2-methyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione(Compound A) or3-(4-((4-(morpholinomethyl)benzyl)oxy)-1-oxoisoindolin-2-yl)piperidine-2,6-dione,a stereoisomer thereof, or a pharmaceutically acceptable salt, solvate,hydrate, co-crystal, clathrate, or polymorph thereof. In certainembodiments of the methods provided herein, the CMA is not thalidomide,lenalidomide, pomalidomide,3-(5-amino-2-methyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione(Compound A) or3-(4-((4-(morpholinomethyl)benzyl)oxy)-1-oxoisoindolin-2-yl)piperidine-2,6-dione,a stereoisomer thereof, or a pharmaceutically acceptable salt, solvate,hydrate, co-crystal, clathrate, or polymorph thereof. In an embodiment,the compound is lenalidomide. In another embodiment, the compound isCompound A. In some embodiments, the compound is not thalidomide. Inother embodiments, the compound is not lenalidomide. In otherembodiments, the compound is not Compound A. In some embodiments, thecompound is not thalidomide, lenalidomide, Compound A, or any analogthereof.

In certain embodiments of the various compositions and methods providedherein, the substrate is a CRBN-associated protein.

In some embodiments, the CRBN-associated protein is Ikaros. In otherembodiments, the CRBN-associated protein is Aiolos. In some embodiments,the CRBN-associated protein is Ikaros and Aiolos. In certainembodiments, the CRBN-associated protein is interferon. In otherembodiments, the CRBN-associated protein is an interferon pathwayprotein. In some embodiments, the interferon pathway protein isinterferon-induced transmembrane protein 3 (IFITM3) and/or interferonregulatory factor 7 (IRF7). In one embodiment of the methods providedherein, the CRBN-associated protein is IKZF3 (Aiolos) having a molecularweight of 58 kDa. In another embodiment of the methods provided herein,the CRBN-associated protein is IKZF3 (Aiolos) having a molecular weightof 42 kDa. Other isoforms of Ikaros and/or Aiolos are also contemplatedherein. In various embodiments of the methods provided herein, theCRBN-associated protein is interferon, an interferon pathway protein,casein kinase 1, alpha 1 (CSNK1A1), or a combination thereof. In otherembodiments, the CRBN-associated protein is DDB1, DDB2, GSK3B, CUL4A,CUL4B, XBP-1, FAS1, RANBP6, DUS3L, PHGDH, AMPK, IRF4 or NFκB. In variousembodiments of the methods provided herein, the CRBN-associated proteinis DDB1, PABPC1, HNRNPR, RPL19, SYNCRIP, H2AFX, HSPA8, ALDOA, HIST1H2AA,HSPA1A, XRCC6, RPL12, RPL18A, RPL4, HNRNPA2B1, HNRNPC, RPS2, SEC24C,RPL9, USP15, SEC24A, CTPS, ABCE1, EEF1A1, IPO5, CPSF6, KCNAB2, C70RF42,SMC4, GNB3, H2AFZ, HIST1H1C, HIST1H1D, HIST1H1E, ACTB, CSNK2A1, CRBN,DDX21, DHX9, DNAJC1, G3BP1, HSPA1B, IGF2BP2, RPL10A, RPL13A, RPL14,RPL15, RPL21, RPL3, RPL30, RPL7, RPL7A, RPLP1, RPLP2, MYH10, ILF3, NCL,RPS13, RPS16, RPS19, RPS6, SND1, EIF2S2, HNRNPH2, UBB, EEF1G, TBL1XR1,NACA, EIF4A1, FASN, PPAT, G3BP2, TUBA1A, UBAP2L, MCM2, UAP1, TUBA1C,EIF2S1, EIF3J, PRKDC, MCM7, RPL11, TUBA1B, STAT3, PTRH2, PABPC4, PTPRC,MACF1, UBE2O, DUT, GNB2L1, NUP88, H2AFJ, SEC23B, PDXK, ACLY, ARID1A,GBE1, HSPA9, DDX17, FUBP1, FBXO21, EWSR1, IFI16, YWHAE, UBA52, COPS6,GNAS, UBE2Q1, FERMT3, NAP1L2, TPD52, VAPA, EEF1AL3, DDIT4, NEDD8,HIST1H1A, HIST1H1B, or PCM1. Other isoforms of the aforementionedCRBN-associated proteins are also contemplated herein.

5.4.1. Inducing a CRBN Conformational Change to Alter SubstrateSpecificity

Also provided herein are methods of inducing a conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein), said method comprising contacting the CRBN with a CMA, whereinsaid CRBN conformational change or alteration results in an alteredsubstrate specificity. In certain embodiments, the altered substratespecificity is as compared to a CRBN in the absence of the CMA. In otherembodiments, the altered substrate specificity is as compared to a CRBNin the presence of a different CMA. In some embodiments, a CRBNconformational change or alteration is induced. In other embodiments, analteration of the properties of a CRBN surface are induced.

In one aspect, provided herein is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or otherwise alters the properties of a CRBN surface (e.g., on anadjacent region of the protein), comprising contacting the CRBN with atest compound, wherein said CRBN conformational change or alterationresults in a different substrate specificity as compared to thesubstrate specificity of a CRBN that is contacted with a referencecompound. In certain embodiments, the conformational change oralteration occurs in a CMA binding pocket of the CRBN. In someembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on W380, W386 and/or W400 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on E377 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on V388 of CRBN. In some embodiments, a CRBN conformationalchange is induced. In other embodiments, an alteration of the propertiesof a CRBN surface are induced. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

Substrate specificity can be assessed using any method known to those inthe art. In some embodiments, substrate specificity is assessed usingUbiScan. In other embodiments, substrate specificity is assessed byquantitating the level of a protein or mRNA of a CRBN-associated proteinas provided elsewhere herein.

5.4.2. Inducing a CRBN Conformational Change to Modulate a BiologicalActivity or Therapeutic Efficacy

In some embodiments, CRBN conformational changes (e.g., within theCMA-binding pocket of the CRBN) or an alteration of the properties of aCRBN surface (e.g., on an adjacent region of the protein) followingcontact with a CMA results in an altered substrate specificity, whereinthe altered substrate specificity, in turn, modulates downstreambiological activity.

Provided herein are methods of inducing a CRBN conformational change(e.g., within the CMA-binding pocket of the CRBN) or otherwise altersthe properties of a CRBN surface (e.g., on an adjacent region of theprotein), said method comprising contacting the CRBN with a CMA, whereinsaid CRBN conformational change or alteration results in modulation of abiological activity in a cell or subject. In some embodiments, a CRBNconformational change is induced. In other embodiments, an alteration ofthe properties of a CRBN surface are induced.

In some embodiments, the conformational change or alteration occurswithin the CMA binding pocket of the CRBN. In certain embodiments, theconformational change or alteration is assessed using any one of themethods provided herein. In certain embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on anadjacent region of the protein.

In another aspect, provided herein is a method of identifying a testcompound that induces a specific biological activity, comprisingcontacting the test compound with CRBN, inducing a CRBN conformationalchange (e.g., within the CMA-binding pocket of the CRBN) or otherwisealters the properties of a CRBN surface (e.g., on an adjacent region ofthe protein), and assessing conformational change or alteration withinthe CMA-binding pocket of the CRBN, wherein conformational change oralteration is indicative of a specific biological activity. In someembodiments, the method further comprises assaying the specificbiological activity. Also provided herein is a test compound identifiedby this method. In certain embodiments, the method further comprisesadministering said compound to a patient, wherein said biologicalactivity is modulated in said patient. In certain embodiments, thepatient has a disease, and wherein one or more symptoms of said diseaseare alleviated following said administration. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the test compound induces a CRBNconformational change or alteration. In other embodiments, the testcompound alters the properties of the CRBN surface. In certainembodiments, the properties of the CRBN surface are altered by theplacement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In some embodiments, the biological activity is a tumoricidal effect. Inone embodiment, the biological activity is modulation of apoptosis. Inother embodiment, the biological activity is modulation ofproliferation, e.g., an anti-proliferative effect. In some embodiments,the biological activity is modulation of PBMC viability. In certainembodiments, the biological activity is modulation of toxicity. In otherembodiments, the biological activity is substrate degradation. Incertain embodiments, the biological activity is degradation of Aiolosand/or Ikaros. In certain embodiments, the biological activity is aprevention of substrate degradation. In some embodiments, the substrateis a CRBN-associated protein. In some embodiments, the biologicalactivity is an immune-mediated effect. In certain embodiments, thebiological effect is modulation of IL-2. In yet other embodiments, thebiological effect is an effect on fetal hemoglobin (HbF). In someembodiments, the effect is an effect on a CRBN-associated protein.

In certain embodiments, a biological activity is observed in one celltype, but not another cell type. In a specific embodiments, thebiological activity is directly correlated with an observed CRBNconformational shift in the cell type(s). In an embodiments, the CRBNconformational shift is in a CMA-binding pocket of CRBN. Suchconformational shifts can be assessed using any of the various methodsprovided elsewhere herein.

In some embodiments, a biological activity is observed in one tissuetype, but not another tissue type. In a specific embodiments, thebiological activity is directly correlated with an observed CRBNconformational shift in the tissue type(s). In an embodiments, the CRBNconformational shift is in a CMA-binding pocket of CRBN. Suchconformational shifts can be assessed using any of the various methodsprovided elsewhere herein.

In certain embodiments, a biological activity is observed in one tumor(or cancer) type, but not another tumor (or cancer) type. In a specificembodiments, the biological activity is directly correlated with anobserved CRBN conformational shift in the tumor (cancer) type(s). In anembodiments, the CRBN conformational shift is in a CMA-binding pocket ofCRBN. Such conformational shifts can be assessed using any of thevarious methods provided elsewhere herein.

In some embodiments, a biological activity is observed in a solid tumor(or cancer), but not in a non-solid tumor (or cancer) (e.g., ahematological tumor). In a specific embodiments, the biological activityis directly correlated with an observed CRBN conformational shift in thetumor(s) (or cancer(s)). In an embodiments, the CRBN conformationalshift is in a CMA-binding pocket of CRBN. Such conformational shifts canbe assessed using any of the various methods provided elsewhere herein.

In some embodiments, a biological activity is observed in a non-solidtumor (or cancer) (e.g., a hematological tumor), but not in a solidtumor (or cancer). In a specific embodiments, the biological activity isdirectly correlated with an observed CRBN conformational shift in thetumor(s) (or cancer(s)). In an embodiments, the CRBN conformationalshift is in a CMA-binding pocket of CRBN. Such conformational shifts canbe assessed using any of the various methods provided elsewhere herein.

In certain embodiments, the solid tumor or cancer is a breast, kidney,ovary, colon, bladder, brain, liver of prostate tumor or cancer. In someembodiments, the non-solid tumor is a blood (hematological) cancer.

In some embodiments, exemplary tumors or cancers include withoutlimitation acute lymphoblastic leukemia, acute myeloid leukemia, Ewing'ssarcoma, gestational trophoblastic carcinoma, Hodgkin's disease,non-Hodgkin's lymphoma, Burkitt's lymphoma diffuse large cell lymphoma,follicular mixed lymphoma, lymphoblastic lymphoma, rhabdomyosarcoma,testicular carcinoma, wilms's tumor, anal carcinoma, bladder carcinoma,breast carcinoma, chronic lymphocytic leukemia, chronic myelogenousleukemia, hairy cell leukemia, head and neck carcinoma, meningioma,neuro fibrosoma, angio fibrosoma, lung (small cell) carcinoma, multiplemyeloma, Non-Hodgkin's lymphoma, follicular lymphoma, ovarian carcinoma,brain tumors (astrocytoma), cervical carcinoma, colorectal carcinoma,hepatocellular carcinoma, human large hepatocellular carcinoma, Kaposi'ssarcoma, lung (non-small-cell) carcinoma, melanoma, pancreaticcarcinoma, prostate carcinoma, soft tissue sarcoma, breast carcinoma,colorectal carcinoma (stage Il), bone tumors, osteogenic sarcoma,ovarian carcinoma, uterine fibroids, testicular carcinoma, orcombinations thereof.

In one aspect, provided herein is a method of inducing a biologicalactivity in a cell comprising CRBN, comprising contacting said cell witha test compound, wherein said compound induces a conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein) of said CRBN, and wherein said CRBN conformational change oralteration is as compared to a reference compound, and wherein theconformational change or alteration results in said biological activity.In some embodiments, a CRBN conformational change or alteration isinduced. In other embodiments, an alteration of the properties of a CRBNsurface are induced. In some embodiments, the biological activity is atumoricidal effect. In other embodiments, the biological activity is anapoptosis effect. In some embodiments, the biological activity isanti-proliferation. In yet other embodiments, the biological activity isPBMC viability. In some embodiments, the biological activity istoxicity. In certain embodiments, the biological activity is substratedegradation. In one embodiments, the biological activity is Aiolosdegradation. In another embodiments, the biological activity is Ikarosdegradation. In other embodiments, the biological activity is animmune-mediated effect. In another embodiment, the biological activityis IL-2 induction. In some embodiments, the biological activity is IL-2repression. In yet other embodiments, the biological activity is a HbFeffect. Any combination of one, two, three or more of the aforementionedbiological activities is also contemplated. In certain embodiments, thebiological activity is based on specific cell type categories. In otherembodiments, the biological activity is based on specific tissue typecategories. In yet other embodiments, the biological activity is basedon solid tumors or solid tumor categories. In some embodiments, thebiological activity is based on non-solid tumor categories. In certainembodiments, the conformational change or alteration occurs in a CMAbinding pocket of the CRBN. In some embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on W380,W386 and/or W400 of CRBN. In other embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on E377 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on V388 of CRBN. In an embodiment,the conformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational is assessedby a method comprising (a) (i) obtaining a first crystal structure ofCRBN and a reference compound, and (ii) determining a three-dimensionalstructure of the first crystal by x-ray diffraction to obtain a firstset of atomic coordinates; (b) (i) obtaining a second crystal comprisingCRBN and the test compound, and (ii) determining a three-dimensionalstructure of the second crystal by x-ray diffraction to obtain a secondset of atomic coordinates; and (c) comparing said first set of atomiccoordinates with said second set of atomic coordinates; wherein adifference in atomic coordinates is indicative of conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein). In certain embodiments, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN and a reference compound; (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. Insome embodiments, the first and/or second three-dimensional structuresinclude a CMA binding domain of the CRBN. In other embodiments, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof. Insome embodiments, the reference compound is an immunomodulatory compoundprovided herein.

In certain embodiments, the biological activity being modulated by theCMA has a direct effect on therapeutic utility of the CMA in a subject.

In one aspect, provided herein is a method of inducing a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or otherwise altering the properties of a CRBN surface (e.g., on anadjacent region of the protein), comprising contacting the CRBN with acompound, wherein said CRBN conformational change or alteration resultsin a specific therapeutic utility. In some embodiments, a CRBNconformational change or alteration is induced. In other embodiments, analteration of the properties of a CRBN surface are induced. In someembodiments, the therapeutic utility is based on solid tumors or solidtumor categories. In other embodiments, the therapeutic utility is basedon non-solid tumor categories. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In another aspect, provided herein is a method of identifying a testcompound that has a specific therapeutic utility, comprising contactingthe test compound with CRBN, inducing a CRBN conformational change(e.g., within the CMA-binding pocket of the CRBN) or otherwise alteringthe properties of a CRBN surface (e.g., on an adjacent region of theprotein), and assessing the conformational change or alteration withinthe CMA-binding pocket of the CRBN, wherein a conformational change oralteration is indicative of the specific therapeutic utility. In someembodiments, a CRBN conformational change is induced. In otherembodiments, an alteration of the properties of a CRBN surface areinduced. Also provided herein is a test compound identified by thismethod. In some embodiments, the method further comprises administeringsaid compound to a patient having a disease, wherein one or moresymptoms of said disease is alleviated following said administration. Incertain embodiments, the conformational change or alteration occurs in aCMA binding pocket of the CRBN. In some embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on W380,W386 and/or W400 of CRBN. In other embodiments, the conformationalchange or alteration in said CMA binding pocket has an effect on E377 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on V388 of CRBN. In an embodiment,the conformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In certain embodiments of the methods provided herein, the contacting instep (a) is performed in vitro. In other embodiments, the contacting instep (a) is performed in vivo. In one embodiment, the CRBN is arecontacted with the compound for a period of time, e.g., 5, 10, 15, 20,25, 30, 35, 40, 45, 50, or 55 minutes, or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24 hours, or 2 or3 or more days.

In some embodiments of the various methods provided herein, thetherapeutic utility is the management or treatment of a CRBN-associateddisease, disorder or a symptom thereof. In other embodiments, thetherapeutic utility is the management or treatment of a cancer or tumor,or a symptom thereof. In some embodiments, the tumor or cancer is aliver cancer, kidney cancer, acute lymphoblastic leukemia, acute myeloidleukemia, Ewing's sarcoma, gestational trophoblastic carcinoma,Hodgkin's disease, non-Hodgkin's lymphoma, Burkitt's lymphoma diffuselarge cell lymphoma, follicular mixed lymphoma, lymphoblastic lymphoma,rhabdomyosarcoma, testicular carcinoma, wilms's tumor, anal carcinoma,bladder carcinoma, breast carcinoma, chronic lymphocytic leukemia,chronic myelogenous leukemia, hairy cell leukemia, head and neckcarcinoma, meningioma, neuro fibrosoma, angio fibrosoma, lung (smallcell) carcinoma, multiple myeloma, Non-Hodgkin's lymphoma, follicularlymphoma, ovarian carcinoma, brain tumors (astrocytoma), cervicalcarcinoma, colorectal carcinoma, hepatocellular carcinoma, human largehepatocellular carcinoma, Kaposi's sarcoma, lung (non-small-cell)carcinoma, melanoma, pancreatic carcinoma, prostate carcinoma, softtissue sarcoma, breast carcinoma, colorectal carcinoma (stage Il), bonetumors, osteogenic sarcoma, ovarian carcinoma, uterine fibroids,testicular carcinoma, or combinations thereof. In some embodiments, thecancer or tumor is a lymphoma, leukemia, multiple myeloma, solid tumor,non-Hodgkin's lymphoma, DLBCL, mantle cell lymphoma, follicularlymphoma, acute myeloblastic leukemia, chronic lymphocytic leukemia, MDSor melanoma.

In another aspect, provided herein is a method of treating oralleviating one or more symptoms of a CRBN-mediated disease or disorderin a patient, comprising administering a test compound to the subject,wherein said compound induces a conformational change or alteration ofsaid CRBN, and wherein said CRBN conformational change or alteration isas compared to a reference compound, and wherein said CRBNconformational change or alteration results in treatment or alleviationof one or more symptoms of said disease or disorder. In certainembodiments, the disease or disorder is a cancer or tumor. In someembodiments, the test compound induces a CRBN conformational change oralteration. In other embodiments, the test compound alters theproperties of the CRBN surface. In certain embodiments, the propertiesof the CRBN surface are altered by the placement of compound appendages.In certain embodiments, the conformational change or alteration occursin a CMA binding pocket of the CRBN. In some embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on W380, W386 and/or W400 of CRBN. In other embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on E377 of CRBN. In other embodiments, the conformational changeor alteration in said CMA binding pocket has an effect on V388 of CRBN.In certain embodiments, the conformational change or alteration in saidCMA binding pocket has an effect on an adjacent region of the protein.In an embodiment, the conformational change or alteration is assessed byx-ray crystallography. In another embodiment, the conformational changeor alteration is assessed by a method comprising (a) (i) obtaining afirst crystal structure of CRBN and a reference compound, and (ii)determining a three-dimensional structure of the first crystal by x-raydiffraction to obtain a first set of atomic coordinates; (b) (i)obtaining a second crystal comprising CRBN and the test compound, and(ii) determining a three-dimensional structure of the second crystal byx-ray diffraction to obtain a second set of atomic coordinates; and (c)comparing said first set of atomic coordinates with said second set ofatomic coordinates; wherein a difference in atomic coordinates isindicative of conformational change (e.g., within the CMA-binding pocketof the CRBN) or alteration of the properties of a CRBN surface (e.g., onan adjacent region of the protein). In certain embodiments, theconformational change is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change. Insome embodiments, the first and/or second three-dimensional structuresinclude a CMA binding domain of the CRBN. In other embodiments, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof. Insome embodiments provided herein is a (test) compound for use in amethod of treating or alleviating one or more symptoms of aCRBN-mediated disease or disorder in a patient, wherein the methodcomprises administering the (test) compound to a patient, wherein saidcompound is as described above.

Also provided herein is a method of alleviating one or more symptoms ofa CRBN-associated disease, disorder, or a symptom thereof, in a patient,comprising administering a compound to the subject, wherein saidcompound induces a CRBN conformational change (e.g., within theCMA-binding pocket of the CRBN) or otherwise alters the properties of aCRBN surface (e.g., on an adjacent region of the protein) in a cell ofsaid subject. In some embodiments, a CRBN conformational change isinduced. In other embodiments, an alteration of the properties of a CRBNsurface are induced. In some embodiments, the CRBN conformational changeor alteration is assessed using a method provided elsewhere herein. Incertain embodiments, the CRBN conformational change or alterationcomprises atomic coordinates as provided in any one of Tables 3-5, orFIGS. 12-18 or 20. In some embodiments, the CRBN conformational changeor alteration results in alleviation of one or more symptoms of saidCRBN-mediated disease or disorder in the patient. In some embodimentsprovided herein is a compound for use in a method of alleviating one ormore symptoms of a CRBN-associated disease, disorder, or a symptomthereof, in a patient, the method comprises administering a compound tothe subject.

In some embodiments of the various methods provided herein, theCRBN-associated disease or disorder is a cancer or tumor. In otherembodiments, the CRBN-associated disease or disorder is not a cancer ortumor. In some embodiments, the tumor or cancer is a liver cancer,kidney cancer, acute lymphoblastic leukemia, acute myeloid leukemia,Ewing's sarcoma, gestational trophoblastic carcinoma, Hodgkin's disease,non-Hodgkin's lymphoma, Burkitt's lymphoma diffuse large cell lymphoma,follicular mixed lymphoma, lymphoblastic lymphoma, rhabdomyosarcoma,testicular carcinoma, wilms's tumor, anal carcinoma, bladder carcinoma,breast carcinoma, chronic lymphocytic leukemia, chronic myelogenousleukemia, hairy cell leukemia, head and neck carcinoma, meningioma,neuro fibrosoma, angio fibrosoma, lung (small cell) carcinoma, multiplemyeloma, Non-Hodgkin's lymphoma, follicular lymphoma, ovarian carcinoma,brain tumors (astrocytoma), cervical carcinoma, colorectal carcinoma,hepatocellular carcinoma, human large hepatocellular carcinoma, Kaposi'ssarcoma, lung (non-small-cell) carcinoma, melanoma, pancreaticcarcinoma, prostate carcinoma, soft tissue sarcoma, breast carcinoma,colorectal carcinoma (stage Il), bone tumors, osteogenic sarcoma,ovarian carcinoma, uterine fibroids, testicular carcinoma, orcombinations thereof. In some embodiments, the cancer or tumor is alymphoma, leukemia, multiple myeloma, solid tumor, non-Hodgkin'slymphoma, DLBCL, mantle cell lymphoma, follicular lymphoma, acutemyeloblastic leukemia, chronic lymphocytic leukemia, MDS or melanoma.

5.4.3. Methods of Assaying a Specific Biological Activity

In certain embodiments of the methods provided herein, the methodcomprises assaying a specific biological activity. In certainembodiments, the biological activity is substrate degradation. Incertain embodiments, the substrate is a CRBN-associated protein. In someembodiments, the CRBN-associated protein is detected and/or quantified.In some embodiments, the methods comprises: (a) contacting the samplewith a first antibody that immunospecifically binds to theCRBN-associated protein; (b) contacting the sample bound to the firstantibody with a second antibody with a detectable label, wherein thesecond antibody immunospecifically binds to the CRBN-associated protein,and wherein the second antibody immunospecifically binds to a differentepitope on CRBN-associated protein than the first antibody; (c)detecting the presence of second antibody bound to the sample; and (d)determining the protein level of the CRBN-associated protein based onthe amount of detectable label in the second antibody. In oneembodiment, the CRBN-associated protein is Ikaros. In anotherembodiment, the CRBN-associated protein is Aiolos. In yet anotherembodiment, the CRBN-associated protein is Ikaros and Aiolos. In yetother embodiments, the CRBN-associated protein is interferon. In otherembodiments, the CRBN-associated protein is an interferon pathwayprotein. In other embodiments, the interferon pathway protein isinterferon-induced transmembrane protein 3 (IFITM3) and/or interferonregulatory factor 7 (IRF7). In yet other embodiments, theCRBN-associated protein is casein kinase 1, alpha 1 (CSNK1A1).

In other embodiments, the method comprises: (a) obtaining RNA from thesample; (b) contacting the RNA with a primer comprising a sequencespecifically binding to a sequence in the RNA to generate a first DNAmolecule having a sequence complementary to said RNA; (c) amplifying theDNA corresponding to a segment of a gene encoding the CRBN-associatedprotein; and (d) determining the RNA level of the CRBN-associatedprotein based on the amount of the amplified DNA. In one embodiment, theCRBN-associated protein is Ikaros. In another embodiment, theCRBN-associated protein is Aiolos. In yet another embodiment, theCRBN-associated protein is Ikaros and Aiolos. In yet other embodiments,the CRBN-associated protein is interferon. In other embodiments, theCRBN-associated protein is an interferon pathway protein. In otherembodiments, the interferon pathway protein is interferon-inducedtransmembrane protein 3 (IFITM3) and/or interferon regulatory factor 7(IRF7). In yet other embodiments, the CRBN-associated protein is caseinkinase 1, alpha 1 (CSNK1A1).

In certain embodiments, the CRBN-associated protein is DDB1, DDB2,GSK3B, CUL4A, CUL4B, XBP-1, FAS1, RANBP6, DUS3L, PHGDH, AMPK, IRF4 orNFκB. In certain embodiments, the CRBN-associated protein is DDB1,PABPC1, HNRNPR, RPL19, SYNCRIP, H2AFX, HSPA8, ALDOA, HIST1H2AA, HSPA1A,XRCC6, RPL12, RPL18A, RPL4, HNRNPA2B1, HNRNPC, RPS2, SEC24C, RPL9,USP15, SEC24A, CTPS, ABCE1, EEF1A1, IPO5, CPSF6, KCNAB2, C70RF42, SMC4,GNB3, H2AFZ, HIST1H1C, HIST1H1D, HIST1H1E, ACTB, CSNK2A1, CRBN, DDX21,DHX9, DNAJC1, G3BP1, HSPA1B, IGF2BP2, RPL10A, RPL13A, RPL14, RPL15,RPL21, RPL3, RPL30, RPL7, RPL7A, RPLP1, RPLP2, MYH10, ILF3, NCL, RPS13,RPS16, RPS19, RPS6, SND1, EIF2S2, HNRNPH2, UBB, EEF1G, TBL1XR1, NACA,EIF4A1, FASN, PPAT, G3BP2, TUBA1A, UBAP2L, MCM2, UAP1, TUBA1C, EIF2S1,EIF3J, PRKDC, MCM7, RPL11, TUBA1B, STAT3, PTRH2, PABPC4, PTPRC, MACF1,UBE20, DUT, GNB2L1, NUP88, H2AFJ, SEC23B, PDXK, ACLY, ARID1A, GBE1,HSPA9, DDX17, FUBP1, FBXO21, EWSR1, IFI16, YWHAE, UBA52, COPS6, GNAS,UBE2Q1, FERMT3, NAP1L2, TPD52, VAPA, EEF1AL3, DDIT4, NEDD8, HIST1H1A,HIST1H1B, PCM1. In some embodiments, these CRBN-associated proteins areevaluated in combination with other CRBN-associated proteins providedherein, such as Ikaros, Aiolos, interferon, an interferon pathwayprotein, and/or casein kinase 1, alpha 1.

In certain embodiments of the various methods provided herein, the twoor more of the steps are performed sequentially. In other embodiments ofthe methods provided herein, two or more of steps are performed inparallel (e.g., at the same time).

Exemplary assays provided herein for the methods of detecting andquantifying the protein level of CRBN-associated protein areimmunoassays such as western blot analysis, and an enzyme-linkedimmunosorbent assay (ELISA) (e.g., a sandwich ELISA). An exemplary assayprovided herein for the methods of detecting and quantifying the RNAlevel of a CRBN-associated protein is reverse transcription polymerasechain reaction (RT-PCR), e.g., quantitative PCR or qPCR.

5.4.4. Types of Cells

In certain embodiments, the biological activity is based on specificcell type categories. Such cells can include any type of cells, e.g.,stem cells, blood cells (e.g., peripheral blood mononuclear cells),lymphocytes, B cells, T cells, monocytes, granulocytes, immune cells, ortumor or cancer cells.

For example, B cells (B lymphocytes) include plasma B cells, memory Bcells, B1 cells, B2 cells, marginal-zone B cells, and follicular Bcells. B cells can express immunoglobulins (antibodies, B cellreceptor). In one embodiment, the cells are Karpas 422, TMD8, WSU-DLCL2,OCI-LY10, Karpas 1106P, HT, SUDHL-10, Riva, OCI-LY19, SUDHL-4, SUDHL-6,OCI-LY3, and Farage.

Specific cell populations can be obtained or assessed using acombination of commercially available antibodies (e.g., Quest Diagnostic(San Juan Capistrano, Calif.); Dako (Denmark)).

In certain embodiments, the cell line is lenalidomide-resistantWSU-DLCL2 or TMD8 cell line. In certain embodiments, the cell line is aDLBCL cell line. In some embodiments, the cell line is a ABC-DLBCL(activated B cell-like DLBCL) cell line, for example, TMD8, OCI-LY10,Riva, or OCI-LY3 cell line. In other embodiments, the cell line is aGCB-DLBCL (germinal center B cell-like DLBCL) cell line, for example,Karpas 422, WSU-DLCL2, Karpas 1106P, HT, SUDHL-10, OCI-LY19, SUDHL-4, orSUDHL-6 cell line.

In some embodiments, the number and type of cells can be monitored, forexample, by measuring changes in morphology and cell surface markersusing standard cell detection techniques such as flow cytometry, cellsorting, immunocytochemistry (e.g., staining with tissue specific orcell-marker specific antibodies) fluorescence activated cell sorting(FACS), magnetic activated cell sorting (MACS), by examination of themorphology of cells using light or confocal microscopy, and/or bymeasuring changes in gene expression using techniques well known in theart, such as PCR and gene expression profiling. These techniques can beused, too, to identify cells that are positive for one or moreparticular markers. Fluorescence activated cell sorting (FACS) is awell-known method for separating particles, including cells, based onthe fluorescent properties of the particles (Kamarch, 1987, MethodsEnzymol, 151:150-165). Laser excitation of fluorescent moieties in theindividual particles results in a small electrical charge allowingelectromagnetic separation of positive and negative particles from amixture. In one embodiment, cell surface marker-specific antibodies orligands are labeled with distinct fluorescent labels. Cells areprocessed through the cell sorter, allowing separation of cells based ontheir ability to bind to the antibodies used. FACS sorted particles maybe directly deposited into individual wells of 96-well or 384-wellplates to facilitate separation and cloning.

In certain embodiments, subsets of cells are used or detected in themethods provided herein. Methods to sort and isolate specificpopulations of cells are well-known in the art and can be based on cellsize, morphology, or intracellular or extracellular markers. Suchmethods include, but are not limited to, flow cytometry, flow sorting,FACS, bead based separation such as magnetic cell sorting, size-basedseparation (e.g., a sieve, an array of obstacles, or a filter), sortingin a microfluidics device, antibody-based separation, sedimentation,affinity adsorption, affinity extraction, density gradientcentrifugation, laser capture microdissection, etc.

In one embodiment, the RNA (e.g., mRNA) or protein is purified and thepresence or absence of a biomarker is measured by gene or proteinexpression analysis. In certain embodiments, the presence or absence ofa biomarker is measured by quantitative real-time PCR (QRT-PCR),microarray, flow cytometry or immunofluorescence. In other embodiments,the presence or absence of a biomarker is measured by enzyme-linkedimmunosorbent assay-based methodologies (ELISA) or other similar methodsknown in the art.

5.4.5. Methods of Detecting mRNA Levels in a Sample

Several methods of detecting or quantitating mRNA levels are known inthe art. Exemplary methods include but are not limited to northernblots, ribonuclease protection assays, PCR-based methods, and the like.The mRNA sequence, e.g., the mRNA of CRBN or CRBN-associated proteins,or a fragment thereof, can be used to prepare a probe that is at leastpartially complementary. The probe can then be used to detect the mRNAsequence in a sample, using any suitable assay, such as PCR-basedmethods, Northern blotting, a dipstick assay, and the like.

In other embodiments, a nucleic acid assay for testing forimmunomodulatory activity in a biological sample can be prepared. Anassay typically contains a solid support and at least one nucleic acidcontacting the support, where the nucleic acid corresponds to at least aportion of an mRNA that has altered expression during animmunomodulatory treatment in a patient, such as the mRNA of CRBN orCRBN-associated proteins. The assay can also have a means for detectingthe altered expression of the mRNA in the sample.

The assay method can be varied depending on the type of mRNA informationdesired. Exemplary methods include but are not limited to Northern blotsand PCR-based methods (e.g., qRT-PCR). Methods such as qRT-PCR can alsoaccurately quantitate the amount of the mRNA in a sample.

Any suitable assay platform can be used to determine the presence of themRNA in a sample. For example, an assay may be in the form of adipstick, a membrane, a chip, a disk, a test strip, a filter, amicrosphere, a slide, a multiwell plate, or an optical fiber. An assaysystem may have a solid support on which a nucleic acid corresponding tothe mRNA is attached. The solid support may comprise, for example, aplastic, silicon, a metal, a resin, glass, a membrane, a particle, aprecipitate, a gel, a polymer, a sheet, a sphere, a polysaccharide, acapillary, a film a plate, or a slide. The assay components can beprepared and packaged together as a kit for detecting an mRNA.

The nucleic acid can be labeled, if desired, to make a population oflabeled mRNAs. In general, a sample can be labeled using methods thatare well known in the art (e.g., using DNA ligase, terminal transferase,or by labeling the RNA backbone, etc.; see, e.g., Ausubel, et al., ShortProtocols in Molecular Biology, 3rd ed., Wiley & Sons 1995 and Sambrooket al., Molecular Cloning: A Laboratory Manual, Third Edition, 2001 ColdSpring Harbor, N.Y.). In some embodiments, the sample is labeled withfluorescent label. Exemplary fluorescent dyes include but are notlimited to xanthene dyes, fluorescein dyes, rhodamine dyes, fluoresceinisothiocyanate (FITC), 6 carboxyfluorescein (FAM), 6carboxy-2′,4′,7′,4,7-hexachlorofluorescein (HEX), 6 carboxy 4′, 5′dichloro 2′, 7′ dimethoxyfluorescein (JOE or J), N,N,N′,N′ tetramethyl 6carboxyrhodamine (TAMRA or T), 6 carboxy X rhodamine (ROX or R), 5carboxyrhodamine 6G (R6G5 or G5), 6 carboxyrhodamine 6G (R6G6 or G6),and rhodamine 110; cyanine dyes, e.g. Cy3, Cy5 and Cy7 dyes; Alexa dyes,e.g. Alexa-fluor-555; coumarin, Diethylaminocoumarin, umbelliferone;benzimide dyes, e.g. Hoechst 33258; phenanthridine dyes, e.g. Texas Red;ethidium dyes; acridine dyes; carbazole dyes; phenoxazine dyes;porphyrin dyes; polymethine dyes, BODIPY dyes, quinoline dyes, Pyrene,Fluorescein Chlorotriazinyl, R110, Eosin, JOE, R6G,Tetramethylrhodamine, Lissamine, ROX, Napthofluorescein, and the like.

In some embodiments, the mRNA sequences comprise at least one mRNAselected from the group consisting of the mRNA of DDB1, PABPC1, HNRNPR,RPL19, SYNCRIP, H2AFX, HSPA8, ALDOA, HIST1H2AA, HSPA1A, XRCC6, RPL12,RPL18A, RPL4, HNRNPA2B1, HNRNPC, RPS2, SEC24C, RPL9, USP15, SEC24A,CTPS, ABCE1, EEF1A1, IPO5, CPSF6, KCNAB2, C70RF42, SMC4, GNB3, H2AFZ,HIST1H1C, HIST1H1D, HIST1H1E, ACTB, CSNK2A1, CRBN, DDX21, DHX9, DNAJC1,G3BP1, HSPA1B, IGF2BP2, RPL10A, RPL13A, RPL14, RPL15, RPL21, RPL3,RPL30, RPL7, RPL7A, RPLP1, RPLP2, MYH10, ILF3, NCL, RPS13, RPS16, RPS19,RPS6, SND1, EIF2S2, HNRNPH2, UBB, EEF1G, TBL1XR1, NACA, EIF4A1, FASN,PPAT, G3BP2, TUBA1A, UBAP2L, MCM2, UAP1, TUBA1C, EIF2S1, EIF3J, PRKDC,MCM7, RPL11, TUBA1B, STAT3, PTRH2, PABPC4, PTPRC, MACF1, UBE20, DUT,GNB2L1, NUP88, H2AFJ, SEC23B, PDXK, ACLY, ARID1A, GBE1, HSPA9, DDX17,FUBP1, FBXO21, EWSR1, IFI16, YWHAE, UBA52, COPS6, GNAS, UBE2Q1, FERMT3,NAP1L2, TPD52, VAPA, EEF1AL3, DDIT4, NEDD8, HIST1H1A, HIST1H1B, PCM1,IKZF1, IKZF3, IFITM3, or CSNK1A1, or a fragment thereof. In oneembodiment, the mRNA is Ikaros mRNA. In another embodiment, the mRNA isAiolos mRNA. In another embodiment, the mRNA is IFITM3 mRNA. In anotherembodiment, the mRNA is CSNK1A1 mRNA. The nucleic acids may be presentin specific, addressable locations on a solid support; eachcorresponding to at least a portion of mRNA sequences that aredifferentially expressed upon treatment of an immunomodulatory compoundin a cell or a patient.

A typical mRNA assay method can contain the steps of 1) obtainingsurface-bound subject probes; 2) hybridization of a population of mRNAsto the surface-bound probes under conditions sufficient to provide forspecific binding (3) post-hybridization washes to remove nucleic acidsnot bound in the hybridization; and (4) detection of the hybridizedmRNAs. The reagents used in each of these steps and their conditions foruse may vary depending on the particular application.

Hybridization can be carried out under suitable hybridizationconditions, which may vary in stringency as desired. Typical conditionsare sufficient to produce probe/target complexes on a solid surfacebetween complementary binding members, i.e., between surface-boundsubject probes and complementary mRNAs in a sample. In certainembodiments, stringent hybridization conditions may be employed.

Hybridization is typically performed under stringent hybridizationconditions. Standard hybridization techniques (e.g. under conditionssufficient to provide for specific binding of target mRNAs in the sampleto the probes) are described in Kallioniemi et al., Science 258:818-821(1992) and WO 93/18186. Several guides to general techniques areavailable, e.g., Tijssen, Hybridization with Nucleic Acid Probes, PartsI and II (Elsevier, Amsterdam 1993). For descriptions of techniquessuitable for in situ hybridizations, see Gall et al. Meth. Enzymol.,21:470-480 (1981); and Angerer et al. in Genetic Engineering: Principlesand Methods (Setlow and Hollaender, Eds.) Vol 7, pgs 43-65 (PlenumPress, New York 1985). Selection of appropriate conditions, includingtemperature, salt concentration, polynucleotide concentration,hybridization time, stringency of washing conditions, and the like willdepend on experimental design, including source of sample, identity ofcapture agents, degree of complementarity expected, etc., and may bedetermined as a matter of routine experimentation for those of ordinaryskill in the art.

Those of ordinary skill will readily recognize that alternative butcomparable hybridization and wash conditions can be utilized to provideconditions of similar stringency.

After the mRNA hybridization procedure, the surface boundpolynucleotides are typically washed to remove unbound nucleic acids.Washing may be performed using any convenient washing protocol, wherethe washing conditions are typically stringent, as described above. Thehybridization of the target mRNAs to the probes is then detected usingstandard techniques.

Other methods, such as PCR-based methods, can also be used to follow theexpression of CRBN or CRB-associated proteins. Examples of PCR methodscan be found in the literature. Examples of PCR assays can be found inU.S. Pat. No. 6,927,024, which is incorporated by reference herein inits entirety. Examples of RT-PCR methods can be found in U.S. Pat. No.7,122,799, which is incorporated by reference herein in its entirety. Amethod of fluorescent in situ PCR is described in U.S. Pat. No.7,186,507, which is incorporated by reference herein in its entirety.

In some embodiments, Real-Time Reverse Transcription-PCR (qRT-PCR) canbe used for both the detection and quantification of RNA targets(Bustin, et al., 2005, Clin. Sci., 109:365-379). Quantitative resultsobtained by qRT-PCR are generally more informative than qualitativedata. Thus, in some embodiments, qRT-PCR-based assays can be useful tomeasure mRNA levels during cell-based assays. The qRT-PCR method is alsouseful to monitor patient therapy. Examples of qRT-PCR-based methods canbe found, for example, in U.S. Pat. No. 7,101,663, which is incorporatedby reference herein in its entirety.

In contrast to regular reverse transcriptase-PCR and analysis by agarosegels, real-time PCR gives quantitative results. An additional advantageof real-time PCR is the relative ease and convenience of use.Instruments for real-time PCR, such as the Applied Biosystems 7500, areavailable commercially, as are the reagents, such as TaqMan SequenceDetection chemistry. For example, TaqMan® Gene Expression Assays can beused, following the manufacturer's instructions. These kits arepre-formulated gene expression assays for rapid, reliable detection andquantification of human, mouse and rat mRNA transcripts. An exemplaryPCR program, for example, is 50° C. for 2 minutes, 95° C. for 10minutes, 40 cycles of 95° C. for 15 seconds, then 60° C. for 1 minute.

To determine the cycle number at which the fluorescence signalassociated with a particular amplicon accumulation crosses the threshold(referred to as the CT), the data can be analyzed, for example, using a7500 Real-Time PCR System Sequence Detection software v1.3 using thecomparative CT relative quantification calculation method. Using thismethod, the output is expressed as a fold-change of expression levels.In some embodiments, the threshold level can be selected to beautomatically determined by the software. In some embodiments, thethreshold level is set to be above the baseline but sufficiently low tobe within the exponential growth region of an amplification curve.

5.4.6. Methods of Detecting Polypeptide or Protein Levels in a Sample

Several protein detection and quantitation methods can be used tomeasure the level of CRBN-associated proteins. Any suitable proteinquantitation method can be used. In some embodiments, antibody-basedmethods are used. Exemplary methods that can be used include but are notlimited to immunoblotting (western blot), enzyme-linked immunosorbentassay (ELISA), immunohistochemistry, flow cytometry, cytometric beadarray, mass spectroscopy, and the like. Several types of ELISA arecommonly used, including direct ELISA, indirect ELISA, and sandwichELISA. In one embodiment, the CRBN-associated protein is Ikaros. Inanother embodiment, the CRBN-associated protein is Aiolos. In anotherembodiment, the CRBN-associated protein is interferon or an interferonpathway protein. In another embodiment, the CRBN-associated protein iscasein kinase 1, alpha 1.

5.5 Substrate CRBN-Modifying Agents as Bridge to Substrate

Also provided herein are methods of using CMA as a bridge or “molecularglue” between CRBN, or a CRBN complex thereof, and a substrate.

Small molecules, such as plant auxins have previously been shown topromote protein-protein interactions in ubiquitin ligases. See, e.g.,Tan et al. (2007) “Mechanism of auxin perception by the TIR1 ubiquitinligase” Nature 446:640-645. Auxins, such as indole-3-acetic acid (IAA),are plant hormones that control many aspects of plant growth. Recentgenetic and molecular studies in Arabidopsis revealed a crucialintracellular auxin signaling pathway in which a ubiquitin-dependentproteolytic system has a key role in sensing and transducing the hormonesignal to transcriptional programs. At the center of the signalingcascade is the ubiquitin-ligase complex, SCF^(TIR1), which promotes theubiquitin-dependent proteolysis of a family of transcriptionalregulators known as Aux/IAAs in an auxin-dependent manner. TIR1, theF-box protein subunit of SCF^(TIR1) functions as the true auxinreceptor. It has been shown that auxin binds directly to SCF^(TIR1) andpromotes the interaction between TIR1 and Aux/IAAs. Usingcrystallographic analysis, Tan et al. showed that TIR1 has a auxin andsubstrate binding pocket, analogous to a three-wall room with an openceiling. The natural auxin, IAA, binds and is tethered to the bottom ofthe TIR1 pocket. IAA7 degron peptide is the natural substrate and docksto the auxin-bound TIR1, enclosing the three-walled TIR1 pocket. Whileauxin binding does not induce significant conformational changes of theTIR1 hormone receptor, auxin does serve to enhance the substrate-bindingactivity of TIR1 by filling a cavity between the two proteins andextending the protein interaction interface. Upon interacting with bothTIR1 and the substrate polypeptide, auxin mediates the formation of acontinuous hydrophobic core among the three proteins, and acts as a“molecular glue” rather than an alosteric switch.

Jasomonites are another family of plant hormones that regulate plangrowth, development and response to stress. See, e.g., Shears et al.(2010) “Jasmonate perception by inositol-phosphate-potentiated COI1-JAZco-receptor” Nature 468:400-407. COI1 shares high homology with TIR1 andis an F-box protein that functions as the substrate-recruiting module ofthe Skp1-Cul1-F-box protein (SCF) ubiquitin E3 ligase complex. Thejasmonate zim domain (JAZ) family of transcriptional repressors areSCF^(COI1) substrate targets, which associate with COI1 in ahormone-dependent manner. Crystallographic studies reveals that thedirect interaction of jasmonite hormones with both the COI1 and JAZprotein is another example of utilization of a “molecular glue”mechanism to enhance the substrate-binding activity of the receptor.

5.6 Substrate Recruitment by CRBN-Modifying Agents

In certain embodiments, provided herein are methods of recruiting asubstrate for ubiquitination by a E3 ubiquitination ligase complexcomprising CRBN. In some embodiments, the method comprises contacting aCRBN with a CMA, resulting in a three-dimensional change of the CRBN(e.g., in the CMA-binding pocket) as provided elsewhere herein. In someembodiments, the method results in a CRBN conformational change. Inother embodiments, the method results in an alteration of the propertiesof a CRBN surface. In a specific embodiment, the CRBN conformationalchange or alteration results in recruitment and ubiquitination of thesubstrate. In certain embodiments, the substrate is not ubiquitinated bythe E3 ubiquitination ligase complex in the absence of the CMA. In oneembodiment, the compound induces a conformational change or alterationhaving atomic coordinates as set forth in any one of Tables 3, 4, 5, 6or 7; or a three dimensional structure as set forth in any one of FIGS.12-18 or 20. In certain embodiments, the conformational change oralteration is as compared to that having atomic coordinates as set forthin any one of Tables 3, 4, 5, 6 or 7; or a three dimensional structureas set forth in any one of FIGS. 12-18 or 20. In certain embodiments, anisoindolinone ring is exposed on the surface of a CRBN-CMA complex. Insome embodiments, the isoindolinone ring of the CRBN-CMA complex formspart of a neomorphic interface in substrate recruitment. In certainembodiments, the unused hydrophobic and/or polar bonding potential ofthe CMA and adjacent protein surface alters substrate recruitment. Inother embodiments, the unused hydrophobic and/or polar bonding potentialof the CMA and adjacent protein surface enhances substrate recruitment.

In a one aspect, provided herein is a method of recruiting a substratefor ubiquitination by a E3 ubiquitination ligase complex comprisingCRBN, said method comprising contacting said CRBN with a compound thatinduces a CRBN conformational change (e.g., within the CMA-bindingpocket of the CRBN) or otherwise alters the properties of a CRBN surface(e.g., on an adjacent region of the protein), wherein said CRBNconformational change or alteration results in recruitment andubiquitination of said substrate; and wherein said substrate is notubiquitinated by said E3 ubiquitination ligase complex in the absence ofsaid compound. In some embodiments, the conformational change oralteration is as compared to the CMA binding pocket when the CRBN iscontacted with a reference compound. In some embodiments, a CRBNconformational change is induced. In other embodiments, an alteration ofthe properties of a CRBN surface are induced. In certain embodiments,the conformational change or alteration occurs in a CMA binding pocketof the CRBN. In some embodiments, the conformational change oralteration in said CMA binding pocket has an effect on W380, W386 and/orW400 of CRBN. In other embodiments, the conformational change oralteration in said CMA binding pocket has an effect on E377 of CRBN. Inother embodiments, the conformational change or alteration in said CMAbinding pocket has an effect on V388 of CRBN. In certain embodiments,the conformational change or alteration in said CMA binding pocket hasan effect on an adjacent region of the protein. In an embodiment, theconformational change or alteration is assessed by x-raycrystallography. In another embodiment, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstcrystal structure of CRBN and a reference compound, and (ii) determininga three-dimensional structure of the first crystal by x-ray diffractionto obtain a first set of atomic coordinates; (b) (i) obtaining a secondcrystal comprising CRBN and the test compound, and (ii) determining athree-dimensional structure of the second crystal by x-ray diffractionto obtain a second set of atomic coordinates; and (c) comparing saidfirst set of atomic coordinates with said second set of atomiccoordinates; wherein a difference in atomic coordinates is indicative ofconformational change (e.g., within the CMA-binding pocket of the CRBN)or alteration of the properties of a CRBN surface (e.g., on an adjacentregion of the protein). In certain embodiments, the conformationalchange or alteration is assessed by a method comprising (a) (i)obtaining a first three-dimensional structure of CRBN and a referencecompound; (b) (i) obtaining a second three-dimensional structure of CRBNand the test compound; and (c) comparing said first three-dimensionalstructure with said second three-dimensional structure; wherein adifference in the first and second three-dimensional structures isindicative of a compound that induces a CRBN conformational change oralteration. In some embodiments, the first and/or secondthree-dimensional structures include a CMA binding domain of the CRBN.In other embodiments, the three-dimensional structure is assessed usingx-ray crystallography, NMR spectroscopy, dual polarizationinterferometry, vibrational spectroscopy, or cryo-elecron microscopy. Insome embodiments, the CRBN is further bound to DDB1, Cul4, Roc1, or anycombination thereof.

In another aspect, provided herein is a method of identifying asubstrate ubiquitinated by a E3 ubiquitination ligase complex comprisingCRBN, said method comprising: (i) contacting said CRBN with a compoundthat induces a CRBN conformational change (e.g., within the CMA-bindingpocket of the CRBN) or otherwise alters the properties of a CRBN surface(e.g., on an adjacent region of the protein), wherein said CRBNconformational change or alteration results in ubiquitination of saidsubstrate, (ii) assaying for ubiquitination of one or more substrates,and (iii) identifying said one or more ubiquitinated substrates; whereinsaid substrate is not ubiquitinated by said E3 ubiquitination ligasecomplex in the absence of said compound. In some embodiments, thecompound induces a CRBN conformational change or alteration. In otherembodiments, the compound alters the properties of the CRBN surface. Incertain embodiments, the properties of the CRBN surface are altered bythe placement of compound appendages. In certain embodiments, theconformational change or alteration occurs in a CMA binding pocket ofthe CRBN. In some embodiments, the conformational change or alterationin said CMA binding pocket has an effect on W380, W386 and/or W400 ofCRBN. In other embodiments, the conformational change or alteration insaid CMA binding pocket has an effect on E377 of CRBN. In otherembodiments, the conformational change or alteration in said CMA bindingpocket has an effect on V388 of CRBN. In certain embodiments, theconformational change or alteration in said CMA binding pocket has aneffect on an adjacent region of the protein. Also provided is asubstrate identified by this method. In some embodiments, theconformational change or alteration is as compared to the CMA bindingpocket when the CRBN is contacted with a reference compound. In certainembodiments, the conformational change or alteration occurs in a CMAbinding pocket of the CRBN. In an embodiment, the conformational changeor alteration is assessed by x-ray crystallography. In anotherembodiment, the conformational change or alteration is assessed by amethod comprising (a) (i) obtaining a first crystal structure of CRBNand a reference compound, and (ii) determining a three-dimensionalstructure of the first crystal by x-ray diffraction to obtain a firstset of atomic coordinates; (b) (i) obtaining a second crystal comprisingCRBN and the test compound, and (ii) determining a three-dimensionalstructure of the second crystal by x-ray diffraction to obtain a secondset of atomic coordinates; and (c) comparing said first set of atomiccoordinates with said second set of atomic coordinates; wherein adifference in atomic coordinates is indicative of conformational change(e.g., within the CMA-binding pocket of the CRBN) or alteration of theproperties of a CRBN surface (e.g., on an adjacent region of theprotein). In certain embodiments, the conformational change oralteration is assessed by a method comprising (a) (i) obtaining a firstthree-dimensional structure of CRBN and a reference compound; (b) (i)obtaining a second three-dimensional structure of CRBN and the testcompound; and (c) comparing said first three-dimensional structure withsaid second three-dimensional structure; wherein a difference in thefirst and second three-dimensional structures is indicative of acompound that induces a CRBN conformational change or alteration. Insome embodiments, the first and/or second three-dimensional structuresinclude a CMA binding domain of the CRBN. In other embodiments, thethree-dimensional structure is assessed using x-ray crystallography, NMRspectroscopy, dual polarization interferometry, vibrationalspectroscopy, or cryo-elecron microscopy. In some embodiments, the CRBNis further bound to DDB1, Cul4, Roc1, or any combination thereof.

5.7 Changes in Substrate Distribution and Abundance

Also provided herein are methods of modulating the distribution patternand/or abundance of a substrate in a cell. In some embodiments, themethod comprises contacting a CRBN with a CMA, resulting in a CRBNconformational change (e.g., within the CMA-binding pocket of the CRBN)or other alteration of the properties of a CRBN surface (e.g., on anadjacent region of the protein), as provided elsewhere herein. In someembodiments, the CRBN has a conformational change. In other embodiments,the CRBN has an alteration of the properties of the CRBN surface. In aspecific embodiment, the CRBN conformational change or alterationresults in a modulation of the distribution pattern of a substrate in acell. In other embodiments, the CRBN conformational change or alterationresults in a modulation of the abundance of a substrate in a cell. Insome embodiments, the modulation is an increase. In other embodiments,the modulation is a decrease. In certain embodiments, the substrate is aCRBN-associated protein.

5.8 Compounds

Compounds for the methods provided herein include, but are not limitedto, the immunomodulatory compounds, including compounds known as“IMiDs®” (Celgene Corporation), a group of compounds that can be usefulto treat several types of human diseases, including certain cancers.

As used herein and unless otherwise indicated, the term“immunomodulatory compound” can encompass certain small organicmolecules that inhibit LPS induced monocyte TNF-α, IL-1β, IL-12, IL-6,MIP-1α, MCP-1, GM-CSF, G-CSF, and COX-2 production. These compounds canbe prepared synthetically, or can be obtained commercially.

Exemplary immunomodulating compounds include but are not limited toN-{[2-(2,6-dioxo(3-piperidyl)-1,3-dioxoisoindolin-4-yl]methyl}cyclopropyl-carboxamide;3-[2-(2,6-dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-4-ylmethyl]-1,1-dimethyl-urea;(−)-3-(3,4-Dimethoxy-phenyl)-3-(1-oxo-1,3-dihydro-isoindol-2-yl)-propionamide;(+)-3-(3,4-Dimethoxy-phenyl)-3-(1-oxo-1,3-dihydro-isoindol-2-yl)-propionamide;(−)-{2-[1-(3-ethoxy-4-methoxyphenyl)-2-methylsulfonylethyl]-4-acetylaminoisoindoline-1,3-dione};(+)-{2-[1-(3-ethoxy-4-methoxyphenyl)-2-methylsulfonylethyl]-4-acetylaminoisoindoline-1,3-dione};Difluoro-methoxy SelCIDs; 1-phthalimido-1-(3,4-diethoxyphenyl)ethane;3-(3,4-dimethoxyphenyl)-3-(3,5-dimethoxyphenyl)acrylo nitrile;1-oxo-2-(2,6-dioxopiperidin-3-yl)-4-aminoisoindoline;1,3-dioxo-2-(2,6-dioxopiperidin-3-yl)-4-aminoisoindoline;4-amino-2-(3-methyl-2,6-dioxo-piperidine-3-yl)-isoindole-1,3-dione;3-(3-acetoamidophthalimido)-3-(3-ethoxy-4-methoxyphenyl)-N-hydroxypropionamide;1-oxo-2-(2,6-dioxopiperidin-3-yl)-4-methylisoindoline;Cyclopropyl-N-{2-[(1S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl]-3-oxoisoindoline-4-yl}carboxamide;Substituted 2-(3-hydroxy-2,6-dioxopiperidin-5-yl) isoindoline;N-[2-(2,6-Dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-5-ylmethyl]-4-trifluoromethoxybenzamide;(S)-4-chloro-N-((2-(3-methyl-2,6-dioxopiperidin-3-yl)-1,3-dioxoisoindolin-5-yl)methyl)benzamide; Pyridine-2-carboxylic acid[2-[(3S)-3-methyl-2,6-dioxo-piperidin-3-yl]-1,3-dioxo-2,3-dihydro-1H-isoindol-5-ylmethyl]-amide;(S)—N-((2-(3-methyl-2,6-dioxopiperidin-3-yl)-1,3-dioxoisoindolin-5-yl)methyl)-4-(trifluoromethyl)benzamide;3-(2,5-dimethyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione, and thelike.

The inflammatory cytokine TNF-α, which is produced by macrophages andmonocytes during acute inflammation, causes a diverse range of signalingevents within cells. Without being limited by a particular theory, oneof the biological effects exerted by the immunomodulatory compoundsdisclosed herein is the reduction of myeloid cell TNF-α production.Immunomodulatory compounds disclosed herein may enhance the degradationof TNF-α mRNA.

Further, without being limited by theory, immunomodulatory compoundsdisclosed herein may also be potent co-stimulators of T cells andincrease cell proliferation dramatically in a dose dependent manner.Immunomodulatory compounds disclosed herein may also have a greaterco-stimulatory effect on the CD8+ T cell subset than on the CD4+ T cellsubset. In addition, the compounds may have anti-inflammatory propertiesagainst myeloid cell responses, yet efficiently co-stimulate T cells toproduce greater amounts of IL-2, IFN-γ, and to enhance T cellproliferation and CD8+ T cell cytotoxic activity. Further, without beinglimited by a particular theory, immunomodulatory compounds disclosedherein may be capable of acting both indirectly through cytokineactivation and directly on Natural Killer (“NK”) cells and NaturalKiller T (“NKT”) cells, and increase the NK cells' ability to producebeneficial cytokines such as, but not limited to, IFN-γ, and to enhanceNK and NKT cell cytotoxic activity.

Specific examples of immunomodulatory compounds include cyano andcarboxy derivatives of substituted styrenes such as those disclosed inU.S. Pat. No. 5,929,117; 1-oxo-2-(2,6-dioxo-3-fluoropiperidin-3yl)isoindolines and 1,3-dioxo-2-(2,6-dioxo-3-fluoropiperidine-3-yl)isoindolines such as those described in U.S. Pat. Nos. 5,874,448 and5,955,476; the tetra substituted2-(2,6-dioxopiperdin-3-yl)-1-oxoisoindolines described in U.S. Pat. No.5,798,368; 1-oxo and 1,3-dioxo-2-(2,6-dioxopiperidin-3-yl) isoindolines(e.g., 4-methyl derivatives of thalidomide), substituted2-(2,6-dioxopiperidin-3-yl) phthalimides and substituted2-(2,6-dioxopiperidin-3-yl)-1-oxoisoindoles including, but not limitedto, those disclosed in U.S. Pat. Nos. 5,635,517, 6,281,230, 6,316,471,6,403,613, 6,476,052 and 6,555,554; 1-oxo and 1,3-dioxoisoindolinessubstituted in the 4- or 5-position of the indoline ring (e.g.,4-(4-amino-1,3-dioxoisoindoline-2-yl)-4-carbamoylbutanoic acid)described in U.S. Pat. No. 6,380,239; isoindoline-1-one andisoindoline-1,3-dione substituted in the 2-position with2,6-dioxo-3-hydroxypiperidin-5-yl (e.g.,2-(2,6-dioxo-3-hydroxy-5-fluoropiperidin-5-yl)-4-aminoisoindolin-1-one)described in U.S. Pat. No. 6,458,810; a class of non-polypeptide cyclicamides disclosed in U.S. Pat. Nos. 5,698,579 and 5,877,200; andisoindole-imide compounds such as those described in U.S. PublicationNo. 2003/0045552 published on Mar. 6, 2003, U.S. Publication No.2003/0096841 published on May 22, 2003, and International ApplicationNo. PCT/US01/50401 (International Publication No. WO 02/059106). U.S.Publication No. 2006/0205787 describes4-amino-2-(3-methyl-2,6-dioxopiperidin-3-yl)-isoindole-1,3-dionecompositions. U.S. Publication No. 2007/0049618 describesisoindole-imide compounds. The entireties of each of the patents andpatent applications identified herein are incorporated by reference. Inone embodiment, immunomodulatory compounds do not include thalidomide.

Various immunomodulatory compounds disclosed herein contain one or morechiral centers, and can exist as racemic mixtures of enantiomers ormixtures of diastereomers. Thus, also provided herein is the use ofstereomerically pure forms of such compounds, as well as the use ofmixtures of those forms. For example, mixtures comprising equal orunequal amounts of the enantiomers of a particular immunomodulatorycompounds may be used. These isomers may be asymmetrically synthesizedor resolved using standard techniques such as chiral columns or chiralresolving agents. See, e.g., Jacques, J., et al., Enantiomers, Racematesand Resolutions (Wiley-Interscience, New York, 1981); Wilen, S. H., etal., Tetrahedron 33:2725 (1977); Eliel, E. L., Stereochemistry of CarbonCompounds (McGraw-Hill, N Y, 1962); and Wilen, S. H., Tables ofResolving Agents and Optical Resolutions p. 268 (E. L. Eliel, Ed., Univ.of Notre Dame Press, Notre Dame, Ind., 1972).

Immunomodulatory compounds provided herein include, but are not limitedto, 1-oxo- and 1,3 dioxo-2-(2,6-dioxopiperidin-3-yl) isoindolinessubstituted with amino in the benzo ring as described in U.S. Pat. No.5,635,517 which is incorporated herein by reference.

These compounds have the structure I:

in which one of X and Y is C═O, the other of X and Y is C═O or CH₂, andR² is hydrogen or lower alkyl, in particular methyl. Specificimmunomodulatory compounds include, but are not limited to:

1-oxo-2-(2,6-dioxopiperidin-3-yl)-4-aminoisoindoline;

1,3-dioxo-2-(2,6-dioxopiperidin-3-yl)-4-aminoisoindoline; and

1,3-dioxo-2-(3-methyl-2,6-dioxopiperidin-3-yl)-4-aminoisoindole, andoptically pure isomers thereof.

The compounds can be obtained via standard, synthetic methods (see e.g.,U.S. Pat. No. 5,635,517, incorporated herein by reference). Thecompounds are also available from Celgene Corporation, Warren, N.J.

Other specific immunomodulatory compounds belong to a class ofsubstituted 2-(2,6-dioxopiperidin-3-yl) phthalimides and substituted2-(2,6-dioxopiperidin-3-yl)-1-oxoisoindoles, such as those described inU.S. Pat. Nos. 6,281,230; 6,316,471; 6,335,349; and 6,476,052, andInternational Patent Application No. PCT/US97/13375 (InternationalPublication No. WO 98/03502), each of which is incorporated herein byreference. Representative compounds are of formula:

in which:one of X and Y is C═O and the other of X and Y is C═O or CH₂;

-   -   (i) each of R¹, R², R³, and R⁴, independently of the others, is        halo, alkyl of 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon        atoms or (ii) one of R¹, R², R³, and R⁴ is —NHR⁵ and the        remaining of R¹, R², R³, and R⁴ are hydrogen;    -   R⁵ is hydrogen or alkyl of 1 to 8 carbon atoms;    -   R⁶ is hydrogen, alkyl of 1 to 8 carbon atoms, benzyl, or halo;    -   provided that R⁶ is other than hydrogen if X and Y are C═O        and (i) each of R¹, R², R³, and R⁴ is fluoro or (ii) one of R¹,        R², R³, or R⁴ is amino.

Compounds representative of this class are of the formulas:

wherein R¹ is hydrogen or methyl. In a separate embodiment, providedherein is the use of enantiomerically pure forms (e.g. optically pure(R) or (S) enantiomers) of these compounds.

Still other specific immunomodulatory compounds disclosed herein belongto a class of isoindole-imides disclosed in U.S. Pat. No. 7,091,353,U.S. Patent Publication No. 2003/0045552, and International ApplicationNo. PCT/US01/50401 (International Publication No. WO 02/059106), each ofwhich are incorporated herein by reference. Representative compounds areof formula II:

and pharmaceutically acceptable salts, hydrates, solvates, clathrates,enantiomers, diastereomers, racemates, and mixtures of stereoisomersthereof, wherein:one of X and Y is C═O and the other is CH₂ or C═O;R¹ is H, (C₁-C₈)alkyl, (C₃-C₇)cycloalkyl, (C₂-C₈)alkenyl,(C₂-C₈)alkynyl, benzyl, aryl, (C₀-C₄)alkyl-(C₁-C₆)heterocycloalkyl,(C₀-C₄)alkyl-(C₂-C₅)heteroaryl, C(O)R³, C(S)R³, C(O)OR⁴,(C₁-C₈)alkyl-N(R⁶)₂, (C₁-C₈)alkyl-OR⁵, (C₁-C₈)alkyl-C(O)OR⁵, C(O)NHR³,C(S)NHR³, C(O)NR³R^(3′), C(S)NR³R³′ or (C₁-C₈)alkyl-O(CO)R⁵;R² is H, F, benzyl, (C₁-C₈)alkyl, (C₂-C₈)alkenyl, or (C₂-C₈)alkynyl;R³ and R^(3′) are independently (C₁-C₈)alkyl, (C₃-C₇)cycloalkyl,(C₂-C₈)alkenyl, (C₂-C₈)alkynyl, benzyl, aryl,(C₀-C₄)alkyl-(C₁-C₆)heterocycloalkyl, (C₀-C₄)alkyl-(C₂-C₅)heteroaryl,(C₀-C₈)alkyl-N(R⁶)₂, (C₁-C₈)alkyl-OR⁵, (C₁-C₈)alkyl-C(O)OR⁵,(C₁-C₈)alkyl-O(CO)R⁵, or C(O)OR⁵;R⁴ is (C₁-C₈)alkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, (C₁-C₄)alkyl-OR⁵,benzyl, aryl, (C₀-C₄)alkyl-(C₁-C₆)heterocycloalkyl, or(C₀-C₄)alkyl-(C₂-C₅)heteroaryl;R⁵ is (C₁-C₈)alkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, benzyl, aryl, or(C₂-C₅)heteroaryl; each occurrence of R⁶ is independently H,(C₁-C₈)alkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, benzyl, aryl,(C₂-C₅)heteroaryl, or (C₀-C₈)alkyl-C(O)O—R⁵ or the R⁶ groups can join toform a heterocycloalkyl group;n is 0 or 1; and* represents a chiral-carbon center.

In specific compounds of formula II, when n is 0 then R¹ is(C₃-C₇)cycloalkyl, (C2-C₈)alkenyl, (C₂-C₈)alkynyl, benzyl, aryl,(C₀-C₄)alkyl-(C₁-C₆)heterocycloalkyl, (C₀-C₄)alkyl-(C₂-C₅)heteroaryl,C(O)R³, C(O)OR⁴, (C₁-C₈)alkyl-N(R⁶)₂, (C₁-C₈)alkyl-OR⁵,(C₁-C₈)alkyl-C(O)OR⁵, C(S)NHR³, or (C₁-C₈)alkyl-O(CO)R⁵;

R² is H or (C₁-C₈)alkyl; andR³ is (C₁-C₈)alkyl, (C₃-C₇)cycloalkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl,benzyl, aryl, (C₀-C₄)alkyl-(C₁-C₆)heterocycloalkyl,(C₀-C₄)alkyl-(C₂-C₅)heteroaryl, (C₅-C₈)alkyl-N(R⁶)2;(C₀-C₈)alkyl-NH—C(O)O—R⁵; (C₁-C₈)alkyl-OR⁵, (C₁-C₈)alkyl-C(O)OR⁵,(C₁-C₈)alkyl-O(CO)R⁵, or C(O)OR⁵; and the other variables have the samedefinitions.

In other specific compounds of formula II, R² is H or (C₁-C₄)alkyl.

In other specific compounds of formula II, R¹ is (C₁-C₈)alkyl or benzyl.

In other specific compounds of formula II, R¹ is H, (C₁-C₈)alkyl,benzyl, CH₂OCH₃, CH₂CH₂OCH₃, or

In another embodiment of the compounds of formula II, R¹ is

wherein Q is O or S, and each occurrence of R⁷ is independently H,(C₁-C₈)alkyl, (C₃-C₇)cycloalkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, benzyl,aryl, halogen, (C₀-C₄)alkyl-(C₁-C₆)heterocycloalkyl,(C₀-C₄)alkyl-(C₂-C₅)heteroaryl, (C₀-C₈)alkyl-N(R⁶)₂, (C₁-C₈)alkyl-OR⁵,(C₁-C₈)alkyl-C(O)OR⁵, (C₁-C₈)alkyl-O(CO)R⁵, or C(O)OR⁵, or adjacentoccurrences of R⁷ can be taken together to form a bicyclic alkyl or arylring.

In other specific compounds of formula II, R¹ is C(O)R³.

In other specific compounds of formula II, R³ is(C₀-C₄)alkyl-(C₂-C₅)heteroaryl, (C₁-C₈)alkyl, aryl, or (C₀-C₄)alkyl-OR⁵.

In other specific compounds of formula II, heteroaryl is pyridyl, furyl,or thienyl.

In other specific compounds of formula II, R¹ is C(O)OR⁴.

In other specific compounds of formula II, the H of C(O)NHC(O) can bereplaced with (C₁-C₄)alkyl, aryl, or benzyl.

Further examples of the compounds in this class include, but are notlimited to:[2-(2,6-dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-4-ylmethyl]-amide;(2-(2,6-dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-4-ylmethyl)-carbamicacid tert-butyl ester;4-(aminomethyl)-2-(2,6-dioxo(3-piperidyl))-isoindoline-1,3-dione;N-(2-(2,6-dioxo-piperidin-3-yl)-1,3-dioxo-2,3-dihydro-1H-isoindol-4-ylmethyl)-acetamide;N-{(2-(2,6-dioxo(3-piperidyl)-1,3-dioxoisoindolin-4-yl)methyl}cyclopropyl-carboxamide;2-chloro-N-{(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)methyl}acetamide;N-(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)-3-pyridylcarboxamide;3-{1-oxo-4-(benzylamino)isoindolin-2-yl}piperidine-2,6-dione;2-(2,6-dioxo(3-piperidyl))-4-(benzylamino)isoindoline-1,3-dione;N-{(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)methyl}propanamide;N-{(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)methyl}-3-pyridylcarboxamide;N-{(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)methyl}heptanamide;N-{(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)methyl}-2-furylcarboxamide;{N-(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)carbamoyl}methylacetate;N-(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)pentanamide;N-(2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl)-2-thienylcarboxamide;N-{[2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl]methyl}(butylamino)carboxamide;N-{[2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl]methyl}(octylamino)carboxamide;andN-{[2-(2,6-dioxo(3-piperidyl))-1,3-dioxoisoindolin-4-yl]methyl}(benzylamino)carboxamide.

Still other specific immunomodulatory compounds disclosed herein belongto a class of isoindole-imides disclosed in U.S. Patent ApplicationPublication Nos. 2002/0045643, International Publication No. WO98/54170, and U.S. Pat. No. 6,395,754, each of which is incorporatedherein by reference. Representative compounds are of formula III:

and pharmaceutically acceptable salts, hydrates, solvates, clathrates,enantiomers, diastereomers, racemates, and mixtures of stereoisomersthereof, wherein:one of X and Y is C═O and the other is CH₂ or C═O;

R is H or CH₂OCOR′;

(i) each of R¹, R², R³, or R⁴, independently of the others, is halo,alkyl of 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon atoms or (ii)one of R¹, R², R³, or R⁴ is nitro or —NHR⁵ and the remaining of R¹, R²,R³, or R⁴ are hydrogen;R⁵ is hydrogen or alkyl of 1 to 8 carbonsR⁶ hydrogen, alkyl of 1 to 8 carbon atoms, benzo, chloro, or fluoro;R′ is R⁷—CHR¹⁰—N(R⁸R⁹);R⁷ is m-phenylene or p-phenylene or —(CnH2n)- in which n has a value of0 to 4; each of R⁸ and R⁹ taken independently of the other is hydrogenor alkyl of 1 to 8 carbon atoms,or R⁸ and R⁹ taken together are tetramethylene, pentamethylene,hexamethylene, or —CH₂CH₂X¹CH₂CH₂— in which X¹ is —O—, —S—, or —NH—;R¹⁰ is hydrogen, alkyl of to 8 carbon atoms, or phenyl; and* represents a chiral-carbon center.

Other representative compounds are of formula:

wherein:one of X and Y is C═O and the other of X and Y is C═O or CH₂;

(i) each of R¹, R², R³, or R⁴, independently of the others, is halo,alkyl of 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon atoms or (ii)one of R¹, R², R³, and R⁴ is —NHR⁵ and the remaining of R¹, R², R³, andR⁴ are hydrogen;

R⁵ is hydrogen or alkyl of 1 to 8 carbon atoms;

R⁶ is hydrogen, alkyl of 1 to 8 carbon atoms, benzo, chloro, or fluoro;

R⁷ is m-phenylene or p-phenylene or —(CnH2n)- in which n has a value of0 to 4;

each of R⁸ and R⁹ taken independently of the other is hydrogen or alkylof 1 to 8 carbon atoms, or R⁸ and R⁹ taken together are tetramethylene,pentamethylene, hexamethylene, or —CH₂CH₂ X¹CH₂CH₂— in which X¹ is —O—,—S—, or —NH—; and

R¹⁰ is hydrogen, alkyl of to 8 carbon atoms, or phenyl.

Other representative compounds are of formula:

in which

one of X and Y is C═O and the other of X and Y is C═O or CH₂;

each of R¹, R², R³, and R⁴, independently of the others, is halo, alkylof 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon atoms or (ii) one ofR¹, R², R³, and R⁴ is nitro or protected amino and the remaining of R¹,R², R³, and R⁴ are hydrogen; and

R⁶ is hydrogen, alkyl of 1 to 8 carbon atoms, benzo, chloro, or fluoro.

Other representative compounds are of formula:

in which:

one of X and Y is C═O and the other of X and Y is C═O or CH₂;

(i) each of R¹, R², R³, and R⁴, independently of the others, is halo,alkyl of 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon atoms or (ii)one of R¹, R², R³, and R⁴ is —NHR⁵ and the remaining of R¹, R², R³, andR⁴ are hydrogen;

R⁵ is hydrogen, alkyl of 1 to 8 carbon atoms, or CO—R⁷—CH(R¹⁰)NR⁸R⁹ inwhich each of R⁷, R⁸, R⁹, and R¹⁰ is as herein defined; and

R⁶ is alkyl of 1 to 8 carbon atoms, benzo, chloro, or fluoro.

Specific examples of the compounds are of formula:

in which:

one of X and Y is C═O and the other of X and Y is C═O or CH₂;

R⁶ is hydrogen, alkyl of 1 to 8 carbon atoms, benzyl, chloro, or fluoro;

R⁷ is m-phenylene, p-phenylene or —(CnH2n)- in which n has a value of 0to 4;

each of R⁸ and R⁹ taken independently of the other is hydrogen or alkylof 1 to 8 carbon atoms, or R⁸ and R⁹ taken together are tetramethylene,pentamethylene, hexamethylene, or —CH₂CH₂X¹CH₂CH₂— in which X¹ is —O—,—S— or —NH—; and

R¹⁰ is hydrogen, alkyl of 1 to 8 carbon atoms, or phenyl.

Other specific immunomodulatory compounds are1-oxo-2-(2,6-dioxo-3-fluoropiperidin-3yl) isoindolines and1,3-dioxo-2-(2,6-dioxo-3-fluoropiperidine-3-yl) isoindolines such asthose described in U.S. Pat. Nos. 5,874,448 and 5,955,476, each of whichis incorporated herein by reference. Representative compounds are offormula:

wherein:Y is oxygen or H₂ andeach of R¹, R², R³, and R⁴, independently of the others, is hydrogen,halo, alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, oramino.

Other specific immunomodulatory compounds are the tetra substituted2-(2,6-dioxopiperdin-3-yl)-1-oxoisoindolines described in U.S. Pat. No.5,798,368, which is incorporated herein by reference. Representativecompounds are of formula:

wherein each of R¹, R², R³, and R⁴, independently of the others, ishalo, alkyl of 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon atoms.

Other specific immunomodulatory compounds are 1-oxo and1,3-dioxo-2-(2,6-dioxopiperidin-3-yl) isoindolines disclosed in U.S.Pat. No. 6,403,613, which is incorporated herein by reference.Representative compounds are of formula:

in which

Y is oxygen or H₂,

a first of R¹ and R² is halo, alkyl, alkoxy, alkylamino, dialkylamino,cyano, or carbamoyl, the second of R¹ and R², independently of thefirst, is hydrogen, halo, alkyl, alkoxy, alkylamino, dialkylamino,cyano, or carbamoyl, and

R³ is hydrogen, alkyl, or benzyl.

Specific examples of the compounds are of formula:

whereina first of R¹ and R² is halo, alkyl of from 1 to 4 carbon atoms, alkoxyof from 1 to 4 carbon atoms, dialkylamino in which each alkyl is of from1 to 4 carbon atoms, cyano, or carbamoyl; the second of R¹ and R²,independently of the first, is hydrogen, halo, alkyl of from 1 to 4carbon atoms, alkoxy of from 1 to 4 carbon atoms, alkylamino in whichalkyl is of from 1 to 4 carbon atoms, dialkylamino in which each alkylis of from 1 to 4 carbon atoms, cyano, or carbamoyl; andR³ is hydrogen, alkyl of from 1 to 4 carbon atoms, or benzyl. Specificexamples include, but are not limited to,1-oxo-2-(2,6-dioxopiperidin-3-yl)-4-methylisoindoline.

Other representative compounds are of formula:

wherein:a first of R¹ and R² is halo, alkyl of from 1 to 4 carbon atoms, alkoxyof from 1 to 4 carbon atoms, dialkylamino in which each alkyl is of from1 to 4 carbon atoms, cyano, or carbamoyl; the second of R¹ and R²,independently of the first, is hydrogen, halo, alkyl of from 1 to 4carbon atoms, alkoxy of from 1 to 4 carbon atoms, alkylamino in whichalkyl is of from 1 to 4 carbon atoms, dialkylamino in which each alkylis of from 1 to 4 carbon atoms, cyano, or carbamoyl; andR³ is hydrogen, alkyl of from 1 to 4 carbon atoms, or benzyl.

Other specific immunomodulatory compounds disclosed herein are 1-oxo and1,3-dioxoisoindolines substituted in the 4- or 5-position of theindoline ring described in U.S. Pat. No. 6,380,239 and U.S. Pat. No.7,244,759, both of which are incorporated herein by reference.Representative compounds are of formula:

in which the carbon atom designated C* constitutes a center of chirality(when n is not zero and R¹ is not the same as R²); one of X¹ and X² isamino, nitro, alkyl of one to six carbons, or NH—Z, and the other of X¹or X² is hydrogen; each of R¹ and R² independent of the other, ishydroxy or NH—Z; R³ is hydrogen, alkyl of one to six carbons, halo, orhaloalkyl; Z is hydrogen, aryl, alkyl of one to six carbons, formyl, oracyl of one to six carbons; and n has a value of 0, 1, or 2; providedthat if X¹ is amino, and n is 1 or 2, then R¹ and R² are not bothhydroxy; and the salts thereof.

Further representative compounds are of formula:

in which the carbon atom designated C* constitutes a center of chiralitywhen n is not zero and R¹ is not R²; one of X¹ and X² is amino, nitro,alkyl of one to six carbons, or NH—Z, and the other of X¹ or X² ishydrogen; each of R¹ and R² independent of the other, is hydroxy orNH—Z;R³ is alkyl of one to six carbons, halo, or hydrogen; Z is hydrogen,aryl or an alkyl or acyl of one to six carbons; and n has a value of 0,1, or 2.

Specific examples include, but are not limited to,2-(4-amino-1-oxo-1,3-dihydro-isoindol-2-yl)-4-carbamoyl-butyric acid and4-(4-amino-1-oxo-1,3-dihydro-isoindol-2-yl)-4-cabamoyl-butyric acid,which have the following structures, respectively, and pharmaceuticallyacceptable salts, solvates, prodrugs, and stereoisomers thereof:

Other representative compounds are of formula:

in which the carbon atom designated C* constitutes a center of chiralitywhen n is not zero and R¹ is not R²; one of X¹ and X² is amino, nitro,alkyl of one to six carbons, or NH—Z, and the other of X¹ or X² ishydrogen; each of R¹ and R² independent of the other, is hydroxy orNH—Z; R³ is alkyl of one to six carbons, halo, or hydrogen; Z ishydrogen, aryl, or an alkyl or acyl of one to six carbons; and n has avalue of 0, 1, or 2; and the salts thereof.

Specific examples include, but are not limited to,4-carbamoyl-4-{4-[(furan-2-yl-methyl)-amino]-1,3-dioxo-1,3-dihydro-isoindol-2-yl}-butyricacid,4-carbamoyl-2-{4-[(furan-2-yl-methyl)-amino]-1,3-dioxo-1,3-dihydro-isoindol-2-yl}-butyricacid,2-{4-[(furan-2-yl-methyl)-amino]-1,3-dioxo-1,3-dihydro-isoindol-2-yl}-4-phenylcarbamoyl-butyricacid, and2-{4-[(furan-2-yl-methyl)-amino]-1,3-dioxo-1,3-dihydro-isoindol-2-yl}-pentanedioicacid, which have the following structures, respectively, andpharmaceutically acceptable salts, solvate, prodrugs, and stereoisomersthereof:

Other specific examples of the compounds are of formula:

wherein:

one of X¹ and X² is nitro, or NH—Z, and the other of X¹ or X² ishydrogen;

each of R¹ and R², independent of the other, is hydroxy or NH—Z;

R³ is alkyl of one to six carbons, halo, or hydrogen;

Z is hydrogen, phenyl, an acyl of one to six carbons, or an alkyl of oneto six carbons; and

n has a value of 0, 1, or 2; and

if —COR² and —(CH₂)_(n)COR¹ are different, the carbon atom designated C*constitutes a center of chirality.

Other representative compounds are of formula:

wherein:

one of X¹ and X² is alkyl of one to six carbons;

each of R¹ and R², independent of the other, is hydroxy or NH—Z;

R³ is alkyl of one to six carbons, halo, or hydrogen;

Z is hydrogen, phenyl, an acyl of one to six carbons, or an alkyl of oneto six carbons; and

n has a value of 0, 1, or 2; and

if —COR² and —(CH₂)_(n)COR¹ are different, the carbon atom designated C*constitutes a center of chirality.

Still other specific immunomodulatory compounds are isoindoline-1-oneand isoindoline-1,3-dione substituted in the 2-position with2,6-dioxo-3-hydroxypiperidin-5-yl described in U.S. Pat. No. 6,458,810,which is incorporated herein by reference. Representative compounds areof formula:

wherein:

the carbon atoms designated * constitute centers of chirality;

X is —C(O)— or —CH₂—;

R¹ is alkyl of 1 to 8 carbon atoms or —NHR³;

R² is hydrogen, alkyl of 1 to 8 carbon atoms, or halogen; and

R³ is hydrogen,

alkyl of 1 to 8 carbon atoms, unsubstituted or substituted with alkoxyof 1 to 8 carbon atoms, halo, amino, or alkylamino of 1 to 4 carbonatoms,

cycloalkyl of 3 to 18 carbon atoms,

phenyl, unsubstituted or substituted with alkyl of 1 to 8 carbon atoms,alkoxy of 1 to 8 carbon atoms, halo, amino, or alkylamino of 1 to 4carbon atoms,

benzyl, unsubstituted or substituted with alkyl of 1 to 8 carbon atoms,alkoxy of 1 to 8 carbon atoms, halo, amino, or alkylamino of 1 to 4carbon atoms, or —COR⁴ in which

R⁴ is hydrogen,

alkyl of 1 to 8 carbon atoms, unsubstituted or substituted with alkoxyof 1 to 8 carbon atoms, halo, amino, or alkylamino of 1 to 4 carbonatoms,

cycloalkyl of 3 to 18 carbon atoms,

phenyl, unsubstituted or substituted with alkyl of 1 to 8 carbon atoms,alkoxy of 1 to 8 carbon atoms, halo, amino, or alkylamino of 1 to 4carbon atoms, or

benzyl, unsubstituted or substituted with alkyl of 1 to 8 carbon atoms,alkoxy of 1 to 8 carbon atoms, halo, amino, or alkylamino of 1 to 4carbon atoms.

Other specific compounds provided herein are of formula:

and pharmaceutically acceptable salts, solvates, and stereoisomersthereof, wherein:

-   R¹ is: hydrogen; halo; —(CH₂)_(n)OH; (C₁-C₆)alkyl, optionally    substituted with one or more halo;    -   (C₁-C₆)alkoxy, optionally substituted with one or more halo; or    -   —(CH₂)_(n)NHR^(a), wherein R^(a) is:        -   hydrogen;        -   (C₁-C₆)alkyl, optionally substituted with one or more halo;        -   —(CH₂)_(n)-(6 to 10 membered aryl); —C(O)—(CH₂)_(n)-(6 to 10            membered aryl) or —C(O)—(CH₂)_(n)-(6 to 10 membered            heteroaryl), wherein the aryl or heteroaryl is optionally            substituted with one or more of: halo; —SCF₃; (C₁-C₆)alkyl,            itself optionally substituted with one or more halo; or            (C₁-C₆)alkoxy, itself optionally substituted with one or            more halo;        -   —C(O)—(C₁-C₈)alkyl, wherein the alkyl is optionally            substituted with one or more halo;        -   —C(O)—(CH₂)_(n)—(C₃-C₁₀-cycloalkyl);        -   —C(O)—(CH₂)_(n)—NR^(b)R^(c), wherein R^(b) and R^(c) are            each independently:            -   hydrogen;            -   (C₁-C₆)alkyl, optionally substituted with one or more                halo;            -   (C₁-C₆)alkoxy, optionally substituted with one or more                halo; or            -   6 to 10 membered aryl, optionally substituted with one                or more of: halo;                -   (C₁-C₆)alkyl, itself optionally substituted with one                    or more halo; or (C₁-C₆)alkoxy, itself optionally                    substituted with one or more halo;        -   —C(O)—(CH₂)_(n)—O—(C₁-C₆)alkyl; or        -   —C(O)—(CH₂)_(n)—O—(CH₂)_(n)-(6 to 10 membered aryl);-   R² is: hydrogen; —(CH₂)_(n)OH; phenyl; —O—(C₁-C₆)alkyl; or    (C₁-C₆)alkyl, optionally substituted with one or more halo;-   R³ is: hydrogen; or (C₁-C₆)alkyl, optionally substituted with one or    more halo; and    -   n is 0, 1, or 2.

Specific examples include, but are not limited to,3-(5-amino-2-methyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione(“Compound A”), which has the following structure:

or an enantiomer or a mixture of enantiomers thereof; or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof.

Compound A can be prepared as described in U.S. Pat. No. 7,635,700, thedisclosure of which is incorporated herein by reference in its entirety.The compound can be also synthesized according to other methods apparentto those of skill in the art based upon the teaching herein. In certainembodiments, Compound A is in a crystalline form described in U.S.Provisional Pat. App. No. 61/451,806, filed Mar. 11, 2011, which isincorporated herein by reference in its entirety. In some embodiments,the hydrochloride salt of Compound A is used in the methods providedherein. Methods of treating, preventing and/or managing cancers andother diseases using Compound A are described in U.S. Provisional Pat.App. No. 61/451,995, filed Mar. 11, 2011, which is incorporated hereinby reference in its entirety.

Specific examples include, but are not limited to lenalidomide, whichhas the following structure:

or an enantiomer or a mixture of enantiomers thereof; or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof.

Lenalidomide can be prepared as described in WO2012/149299, thedisclosure of which is incorporated herein by reference in its entirety.The compound can be also synthesized according to other methods apparentto those of skill in the art based upon the teaching herein.

Other specific compounds provided herein are of formula:

or a pharmaceutically acceptable salt, solvate or stereoisomer thereof,wherein:

X is C═O or CH₂;

R¹ is —Y—R³;R² is H or (C₁-C₆)alkyl;Y is: 6 to 10 membered aryl, heteroaryl or heterocycle, each of whichmay be optionally substituted with one or more halogen; or a bond;R³ is: —(CH₂)n-aryl, —O—(CH₂)n-aryl or —(CH₂)n-O-aryl, wherein the arylis optionally substituted with one or more: (C₁-C₆)alkyl, itselfoptionally substituted with one or more halogen; (C₁-C₆)alkoxy, itselfsubstituted with one or more halogen; oxo; amino; carboxyl; cyano;hydroxyl; halogen; deuterium; 6 to 10 membered aryl or heteroaryl,optionally substituted with one or more (C₁-C₆)alkyl, (C₁-C₆)alkoxy orhalogen; —CONH₂; or —COO—(C₁-C₆)alkyl, wherein the alkyl may beoptionally substituted with one or more halogen;—(CH₂)_(n)-heterocycle, —O—(CH₂)_(n)-heterocycle or—(CH₂)_(n)—O-heterocycle, wherein the heterocycle is optionallysubstituted with one or more: (C₁-C₆)alkyl, itself optionallysubstituted with one or more halogen; (C₁-C₆)alkoxy, itself substitutedwith one or more halogen; oxo; amino; carboxyl; cyano; hydroxyl;halogen; deuterium; 6 to 10 membered aryl or heteroaryl, optionallysubstituted with one or more (C₁-C₆)alkyl, (C₁-C₆)alkoxy or halogen;—CONH₂; or —COO—(C₁-C₆)alkyl, wherein the alkyl may be optionallysubstituted with one or more halogen; or —(CH₂)_(n)-heteroaryl,—O—(CH₂)_(n)-heteroaryl or —(CH₂)_(n)—O-heteroaryl, wherein theheteroaryl is optionally substituted with one or more: (C₁-C₆)alkyl,itself optionally substituted with one or more halogen; (C₁-C₆)alkoxy,itself substituted with one or more halogen; oxo; amino; carboxyl;cyano; hydroxyl; halogen; deuterium; 6 to 10 membered aryl orheteroaryl, optionally substituted with one or more (C₁-C₆)alkyl,(C₁-C₆)alkoxy or halogen; —CONH₂; or —COO—(C₁-C₆)alkyl, wherein thealkyl may be optionally substituted with one or more halogen; andn is 0, 1, 2 or 3.

All of the compounds described can either be commercially purchased orprepared according to the methods described in the patents or patentpublications disclosed herein. Further, optically pure compounds can beasymmetrically synthesized or resolved using known resolving agents orchiral columns as well as other standard synthetic organic chemistrytechniques. Additional information on immunomodulatory compounds, theirpreparation, and use can be found, for example, in U.S. PatentApplication Publication Nos. 2006/0188475, 2006/0205787, and2007/0049618, each of which is incorporated by reference herein in itsentirety.

The compounds may be small organic molecules having a molecular weightless than about 1,000 g/mol, and are not proteins, peptides,oligonucleotides, oligosaccharides or other macromolecules.

In certain embodiments of the various compositions and methods providedherein, a CMA is an immunomodulatory compound provided herein. In otherembodiments, a CMA is not an immunomodulatory compound provided herein.

It should be noted that if there is a discrepancy between a depictedstructure and a name given that structure, the depicted structure is tobe accorded more weight. In addition, if the stereochemistry of astructure or a portion of a structure is not indicated with, forexample, bold or dashed lines, the structure or portion of the structureis to be interpreted as encompassing all stereoisomers of it.

5.9 Treatment for Patients with a CRBN-mediated Disease

Also provided herein is a method of treating and preventing aCRBN-mediated disease, which comprises administering to a patient acompound provided herein, or an enantiomer or a mixture of enantiomersthereof, or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof. In certain embodiments, theCRBN-mediated disease or disorder is a cancer. In certain embodimentsprovided herein is a compound provided herein for use in a method oftreating and preventing a CRBN-mediated disease, the method comprisesadministering to a patient the compound, or an enantiomer or a mixtureof enantiomers thereof, or a pharmaceutically acceptable salt, solvate,hydrate, co-crystal, clathrate, or polymorph thereof.

In another embodiment, provided herein is method of managing aCRBN-mediated disease, which comprises administering to a patient acompound provided herein, or an enantiomer or a mixture of enantiomersthereof, or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof. In certain embodiments, theCRBN-mediated disease or disorder is a cancer. In certain embodimentsprovided herein is a compound provided herein for use in a method ofmanaging a CRBN-mediated disease, the method comprises administering toa patient the compound, or an enantiomer or a mixture of enantiomersthereof, or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof.

Provided herein are methods of treating or managing lymphoma,particularly non-Hodgkin's lymphoma. In some embodiments, providedherein are methods for the treatment or management of non-Hodgkin'slymphoma (NHL), including but not limited to, diffuse large B-celllymphoma (DLBCL), using prognostic factors. In certain embodimentsprovided herein is a compound provided herein for use in a method oftreating or managing lymphoma, particularly non-Hodgkin's lymphoma.

Also provided herein are methods of treating patients who have beenpreviously treated for a CRBN-mediated disease or disorder (e.g., acancer) but are non-responsive to standard therapies, as well as thosewho have not previously been treated. Also provided herein are methodsof treating patients regardless of patient's age, although some diseasesor disorders are more common in certain age groups. Also provided hereinare methods of treating patients who have undergone surgery in anattempt to treat the disease or condition at issue, as well as those whohave not. In some embodiments provided herein a compounds providedherein for use in methods of treating patients as mentioned above.

Because patients with cancer have heterogeneous clinical manifestationsand varying clinical outcomes, the treatment given to a patient mayvary, depending on his/her prognosis. The skilled clinician will be ableto readily determine without undue experimentation specific secondaryagents, types of surgery, and types of non-drug based standard therapythat can be effectively used to treat an individual patient with cancer.

As used herein, the term “cancer” includes, but is not limited to, solidtumors and blood born tumors. The term “cancer” refers to disease ofskin tissues, organs, blood, and vessels, including, but not limited to,cancers of the bladder, bone, blood, brain, breast, cervix, chest,colon, endrometrium, esophagus, eye, head, kidney, liver, lymph nodes,lung, mouth, neck, ovaries, pancreas, prostate, rectum, stomach, testis,throat, and uterus. Specific cancers include, but are not limited to,advanced malignancy, amyloidosis, neuroblastoma, meningioma,hemangiopericytoma, multiple brain metastase, glioblastoma multiforms,glioblastoma, brain stem glioma, poor prognosis malignant brain tumor,malignant glioma, recurrent malignant giolma, anaplastic astrocytoma,anaplastic oligodendroglioma, neuroendocrine tumor, rectaladenocarcinoma, Dukes C & D colorectal cancer, unresectable colorectalcarcinoma, metastatic hepatocellular carcinoma, Kaposi's sarcoma,karotype acute myeloblastic leukemia, Hodgkin's lymphoma, non-Hodgkin'slymphoma, cutaneous T-Cell lymphoma, cutaneous B-Cell lymphoma, diffuselarge B-Cell lymphoma, low grade follicular lymphoma, malignantmelanoma, malignant mesothelioma, malignant pleural effusionmesothelioma syndrome, peritoneal carcinoma, papillary serous carcinoma,gynecologic sarcoma, soft tissue sarcoma, scleroderma, cutaneousvasculitis, Langerhans cell histiocytosis, leiomyosarcoma,fibrodysplasia ossificans progressive, hormone refractory prostatecancer, resected high-risk soft tissue sarcoma, unrescectablehepatocellular carcinoma, Waldenstrom's macroglobulinemia, smolderingmyeloma, indolent myeloma, fallopian tube cancer, androgen independentprostate cancer, androgen dependent stage IV non-metastatic prostatecancer, hormone-insensitive prostate cancer, chemotherapy-insensitiveprostate cancer, papillary thyroid carcinoma, follicular thyroidcarcinoma, medullary thyroid carcinoma, and leiomyoma

In certain embodiments, the cancer is a blood borne tumor. In certainembodiments, the blood borne tumor is metastatic. In certainembodiments, the blood borne tumor is drug resistant. In certainembodiments, the cancer is myeloma or lymphoma.

In certain embodiments, the cancer is a solid tumor. In certainembodiments, the solid tumor is metastatic. In certain embodiments, thesolid tumor is drug-resistant. In certain embodiments, the solid tumoris hepatocellular carcinoma, prostate cancer, ovarian cancer, orglioblastoma.

In one embodiment, provided herein are methods of preventingrelapsed/refractory multiple myeloma in patients with impaired renalfunction or a symptom thereof, comprising administering an effectiveamount of a compound provided herein, or an enantiomer or a mixture ofenantiomers thereof, or a pharmaceutically acceptable salt, solvate,hydrate, stereoisomer, tautomer or racemic mixtures thereof to a patientat risk of having relapsed/refractory multiple myeloma with impairedrenal function. In one embodiment provided herein are compounds providedherein for use in the above-mentioned methods.

In certain embodiments, provided herein are methods for treating,preventing, and/or managing relapsed/refractory multiple myeloma inpatients with impaired renal function. In certain embodiments providedherein are compounds provided herein for use in methods for treating,preventing, and/or managing relapsed/refractory multiple myeloma inpatients with impaired renal function.

In certain embodiments, a therapeutically or prophylactically effectiveamount of the compound is from about 0.005 to about 1,000 mg per day,from about 0.01 to about 500 mg per day, from about 0.01 to about 250 mgper day, from about 0.01 to about 100 mg per day, from about 0.1 toabout 100 mg per day, from about 0.5 to about 100 mg per day, from about1 to about 100 mg per day, from about 0.01 to about 50 mg per day, fromabout 0.1 to about 50 mg per day, from about 0.5 to about 50 mg per day,from about 1 to about 50 mg per day, from about 0.02 to about 25 mg perday, or from about 0.05 to about 10 mg per day.

In certain embodiment, a therapeutically or prophylactically effectiveamount is from about 0.005 to about 1,000 mg per day, from about 0.01 toabout 500 mg per day, from about 0.01 to about 250 mg per day, fromabout 0.01 to about 100 mg per day, from about 0.1 to about 100 mg perday, from about 0.5 to about 100 mg per day, from about 1 to about 100mg per day, from about 0.01 to about 50 mg per day, from about 0.1 toabout 50 mg per day, from about 0.5 to about 50 mg per day, from about 1to about 50 mg per day, from about 0.02 to about 25 mg per day, or fromabout 0.05 to about 10 mg every other day.

In certain embodiments, the therapeutically or prophylacticallyeffective amount is about 0.1, about 0.2, about 0.3. about 0.5, about 1,about 2, about 5, about 10, about 15, about 20, about 25, about 30,about 40, about 45, about 50, about 60, about 70, about 80, about 90,about 100, or about 150 mg per day.

In one embodiment, the recommended daily dose range of a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, for the conditions described herein liewithin the range of from about 0.5 mg to about 50 mg per day, preferablygiven as a single once-a-day dose, or in divided doses throughout a day.In some embodiments, the dosage ranges from about 1 mg to about 50 mgper day. In other embodiments, the dosage ranges from about 0.5 to about5 mg per day. Specific doses per day include 0.01, 0.05, 0.1, 0.2, 0.3,0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 mg per day.

In a specific embodiment, the recommended starting dosage may be 0.01,0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 1, 2, 3, 4, 5, 10, 15, 20, 25 or 50 mgper day. In another embodiment, the recommended starting dosage may be0.5, 1, 2, 3, 4, or 5 mg per day. The dose may be escalated to 15, 20,25, 30, 35, 40, 45 and 50 mg/day. In a specific embodiment, the compoundcan be administered in an amount of about 25 mg/day to patients with NHL(e.g., DLBCL). In a particular embodiment, the compound can beadministered in an amount of about 10 mg/day to patients with NHL (e.g.,DLBCL).

In certain embodiments, the therapeutically or prophylacticallyeffective amount is from about 0.001 to about 100 mg/kg/day, from about0.01 to about 50 mg/kg/day, from about 0.01 to about 25 mg/kg/day, fromabout 0.01 to about 10 mg/kg/day, from about 0.01 to about 9 mg/kg/day,0.01 to about 8 mg/kg/day, from about 0.01 to about 7 mg/kg/day, fromabout 0.01 to about 6 mg/kg/day, from about 0.01 to about 5 mg/kg/day,from about 0.01 to about 4 mg/kg/day, from about 0.01 to about 3mg/kg/day, from about 0.01 to about 2 mg/kg/day, or from about 0.01 toabout 1 mg/kg/day.

The administered dose can also be expressed in units other thanmg/kg/day. For example, doses for parenteral administration can beexpressed as mg/m²/day. One of ordinary skill in the art would readilyknow how to convert doses from mg/kg/day to mg/m²/day to given eitherthe height or weight of a subject or both. For example, a dose of 1mg/kg/day for a 65 kg human is approximately equal to 38 mg/m²/day.

In certain embodiments, the amount of the compound administered issufficient to provide a plasma concentration of the compound at steadystate, ranging from about 0.001 to about 500 μM, about 0.002 to about200 μM, about 0.005 to about 100 μM, about 0.01 to about 50 μM, fromabout 1 to about 50 μM, about 0.02 to about 25 μM, from about 0.05 toabout 20 μM, from about 0.1 to about 20 μM, from about 0.5 to about 20μM, or from about 1 to about 20 μM.

In other embodiments, the amount of the compound administered issufficient to provide a plasma concentration of the compound at steadystate, ranging from about 5 to about 100 nM, about 5 to about 50 nM,about 10 to about 100 nM, about 10 to about 50 nM or from about 50 toabout 100 nM.

As used herein, the term “plasma concentration at steady state” is theconcentration reached after a period of administration of a compoundprovided herein, e.g., a compound provided herein, or an enantiomer or amixture of enantiomers thereof, or a pharmaceutically acceptable salt,solvate, hydrate, co-crystal, clathrate, or polymorph thereof. Oncesteady state is reached, there are minor peaks and troughs on the timedependent curve of the plasma concentration of the compound.

In certain embodiments, the amount of the compound administered issufficient to provide a maximum plasma concentration (peakconcentration) of the compound, ranging from about 0.001 to about 500μM, about 0.002 to about 200 μM, about 0.005 to about 100 μM, about 0.01to about 50 μM, from about 1 to about 50 μM, about 0.02 to about 25 μM,from about 0.05 to about 20 μM, from about 0.1 to about 20 μM, fromabout 0.5 to about 20 μM, or from about 1 to about 20 μM.

In certain embodiments, the amount of the compound administered issufficient to provide a minimum plasma concentration (troughconcentration) of the compound, ranging from about 0.001 to about 500μM, about 0.002 to about 200 μM, about 0.005 to about 100 μM, about 0.01to about 50 μM, from about 1 to about 50 μM, about 0.01 to about 25 μM,from about 0.01 to about 20 μM, from about 0.02 to about 20 μM, fromabout 0.02 to about 20 μM, or from about 0.01 to about 20 μM.

In certain embodiments, the amount of the compound administered issufficient to provide an area under the curve (AUC) of the compound,ranging from about 100 to about 100,000 ng*hr/mL, from about 1,000 toabout 50,000 ng*hr/mL, from about 5,000 to about 25,000 ng*hr/mL, orfrom about 5,000 to about 10,000 ng*hr/mL.

In certain embodiments, the patient to be treated with one of themethods provided herein has not been treated with anticancer therapyprior to the administration of a compound provided herein, or anenantiomer or a mixture of enantiomers thereof, or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof. In certain embodiments, the patient to be treated with one ofthe methods provided herein has been treated with anticancer therapyprior to the administration of a compound provided herein, or anenantiomer or a mixture of enantiomers thereof, or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof. In certain embodiments, the patient to be treated with one ofthe methods provided herein has developed drug resistance to theanticancer therapy.

The methods provided herein encompass treating a patient regardless ofpatient's age, although some diseases or disorders are more common incertain age groups. Further provided herein is a method for treating apatient who has undergone surgery in an attempt to treat the disease orcondition at issue, as well in one who has not. Because the subjectswith cancer have heterogeneous clinical manifestations and varyingclinical outcomes, the treatment given to a particular subject may vary,depending on his/her prognosis. The skilled clinician will be able toreadily determine without undue experimentation, specific secondaryagents, types of surgery, and types of non-drug based standard therapythat can be effectively used to treat an individual subject with cancer.

Depending on the disease to be treated and the subject's condition, acompound provided herein, or an enantiomer or a mixture of enantiomersthereof; or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof, may be administered byoral, parenteral (e.g., intramuscular, intraperitoneal, intravenous,CIV, intracistemal injection or infusion, subcutaneous injection, orimplant), inhalation, nasal, vaginal, rectal, sublingual, or topical(e.g., transdermal or local) routes of administration. A compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof;or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, may be formulated, alone or together,in suitable dosage unit with pharmaceutically acceptable excipients,carriers, adjuvants and vehicles, appropriate for each route ofadministration.

In one embodiment, a compound provided herein, or an enantiomer or amixture of enantiomers thereof; or a pharmaceutically acceptable salt,solvate, hydrate, co-crystal, clathrate, or polymorph thereof, isadministered orally. In another embodiment, a compound provided herein,or an enantiomer or a mixture of enantiomers thereof; or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered parenterally. In yetanother embodiment, a compound provided herein, or an enantiomer or amixture of enantiomers thereof; or a pharmaceutically acceptable salt,solvate, hydrate, co-crystal, clathrate, or polymorph thereof, isadministered intravenously.

A compound provided herein, or an enantiomer or a mixture of enantiomersthereof; or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof, can be delivered as asingle dose such as, e.g., a single bolus injection, or oral tablets orpills; or over time, such as, e.g., continuous infusion over time ordivided bolus doses over time. The compound can be administeredrepeatedly if necessary, for example, until the patient experiencesstable disease or regression, or until the patient experiences diseaseprogression or unacceptable toxicity. For example, stable disease forsolid tumors generally means that the perpendicular diameter ofmeasurable lesions has not increased by 25% or more from the lastmeasurement. Response Evaluation Criteria in Solid Tumors (RECIST)Guidelines, Journal of the National Cancer Institute 92(3): 205-216(2000). Stable disease or lack thereof is determined by methods known inthe art such as evaluation of patient symptoms, physical examination,visualization of the tumor that has been imaged using X-ray, CAT, PET,or MRI scan and other commonly accepted evaluation modalities.

A compound provided herein, or an enantiomer or a mixture of enantiomersthereof; or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof, can be administered oncedaily (QD), or divided into multiple daily doses such as twice daily(BID), three times daily (TID), and four times daily (QID). In addition,the administration can be continuous (i.e., daily for consecutive daysor every day), intermittent, e.g., in cycles (i.e., including days,weeks, or months of rest without drug). As used herein, the term “daily”is intended to mean that a therapeutic compound is administered once ormore than once each day, for example, for a period of time. The term“continuous” is intended to mean that a therapeutic compound isadministered daily for an uninterrupted period of at least 10 days to 52weeks. The term “intermittent” or “intermittently” as used herein isintended to mean stopping and starting at either regular or irregularintervals. For example, intermittent administration of a compoundprovided herein is administration for one to six days per week,administration in cycles (e.g., daily administration for two to eightconsecutive weeks, then a rest period with no administration for up toone week), or administration on alternate days. The term “cycling” asused herein is intended to mean that a therapeutic compound isadministered daily or continuously but with a rest period.

In some embodiments, the frequency of administration is in the range ofabout a daily dose to about a monthly dose. In certain embodiments,administration is once a day, twice a day, three times a day, four timesa day, once every other day, twice a week, once every week, once everytwo weeks, once every three weeks, or once every four weeks. In oneembodiment, a compound provided herein, or an enantiomer or a mixture ofenantiomers thereof; or a pharmaceutically acceptable salt, solvate,hydrate, co-crystal, clathrate, or polymorph thereof, is administeredonce a day. In another embodiment, a compound provided herein, or anenantiomer or a mixture of enantiomers thereof; or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof, is administered twice a day. In yet another embodiment, acompound provided herein, or an enantiomer or a mixture of enantiomersthereof; or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof, is administered three timesa day. In still another embodiment, a compound provided herein, or anenantiomer or a mixture of enantiomers thereof; or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof, is administered four times a day.

In certain embodiments, a compound provided herein, or an enantiomer ora mixture of enantiomers thereof; or a pharmaceutically acceptable salt,solvate, hydrate, co-crystal, clathrate, or polymorph thereof, isadministered once per day from one day to six months, from one week tothree months, from one week to four weeks, from one week to three weeks,or from one week to two weeks. In certain embodiments, a compoundprovided herein, or a pharmaceutically acceptable salt or solvatethereof, is administered once per day for one week, two weeks, threeweeks, or four weeks. In one embodiment, a compound provided herein, oran enantiomer or a mixture of enantiomers thereof; or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof, is administered once per day for one week. In anotherembodiment, a compound provided herein, or an enantiomer or a mixture ofenantiomers thereof; or a pharmaceutically acceptable salt, solvate,hydrate, co-crystal, clathrate, or polymorph thereof, is administeredonce per day for two weeks. In yet another embodiment, a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof;or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered once per day for threeweeks. In still another embodiment, a compound provided herein, or anenantiomer or a mixture of enantiomers thereof; or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof, is administered once per day for four weeks.

5.10 Combination Therapy with a Second Active Agent

A compound provided herein, or an enantiomer or a mixture of enantiomersthereof; or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof, can also be combined orused in combination with other therapeutic agents useful in thetreatment and/or prevention of cancer described herein.

As used herein, the term “in combination” includes the use of more thanone therapy (e.g., one or more prophylactic and/or therapeutic agents).However, the use of the term “in combination” does not restrict theorder in which therapies (e.g., prophylactic and/or therapeutic agents)are administered to a patient with a disease or disorder. A firsttherapy (e.g., a prophylactic or therapeutic agent such as a compoundprovided herein, a compound provided herein, e.g., a compound providedherein, or an enantiomer or a mixture of enantiomers thereof, or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof) can be administered prior to (e.g., 5minutes, 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6hours, 12 hours, 24 hours, 48 hours, 72 hours, 96 hours, 1 week, 2weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 8 weeks, or 12 weeks before),concomitantly with, or subsequent to (e.g., 5 minutes, 15 minutes, 30minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24hours, 48 hours, 72 hours, 96 hours, 1 week, 2 weeks, 3 weeks, 4 weeks,5 weeks, 6 weeks, 8 weeks, or 12 weeks after) the administration of asecond therapy (e.g., a prophylactic or therapeutic agent) to thesubject. Triple therapy is also contemplated herein.

Administration of a compound provided herein and one or more secondactive agents to a patient can occur simultaneously or sequentially bythe same or different routes of administration. The suitability of aparticular route of administration employed for a particular activeagent will depend on the active agent itself (e.g., whether it can beadministered orally without decomposing prior to entering the bloodstream) and the cancer being treated.

The route of administration of a compound provided herein is independentof the route of administration of a second therapy. In one embodiment, acompound provided herein is administered orally. In another embodiment,a compound provided herein is administered intravenously. Thus, inaccordance with these embodiments, a compound provided herein isadministered orally or intravenously, and the second therapy can beadministered orally, parenterally, intraperitoneally, intravenously,intraarterially, transdermally, sublingually, intramuscularly, rectally,transbuccally, intranasally, liposomally, via inhalation, vaginally,intraoccularly, via local delivery by catheter or stent, subcutaneously,intraadiposally, intraarticularly, intrathecally, or in a slow releasedosage form. In one embodiment, a compound provided herein and a secondtherapy are administered by the same mode of administration, orally orby IV. In another embodiment, a compound provided herein is administeredby one mode of administration, e.g., by IV, whereas the second agent (ananticancer agent) is administered by another mode of administration,e.g., orally.

In one embodiment, the second active agent is administered intravenouslyor subcutaneously and once or twice daily in an amount of from about 1to about 1000 mg, from about 5 to about 500 mg, from about 10 to about350 mg, or from about 50 to about 200 mg. The specific amount of thesecond active agent will depend on the specific agent used, the type ofdisease being treated or managed, the severity and stage of disease, andthe amount of a compound provided herein provided herein and anyoptional additional active agents concurrently administered to thepatient. In certain embodiments, the second active agent is oblimersen(GENASENSE®), GM-CSF, G-CSF, SCF, EPO, taxotere, irinotecan,dacarbazine, transretinoic acid, topotecan, pentoxifylline,ciprofloxacin, dexamethasone, vincristine, doxorubicin, COX-2 inhibitor,IL2, IL8, IL18, IFN, Ara-C, vinorelbine, or a combination thereof.

In certain embodiments, GM-CSF, G-CSF, SCF or EPO is administeredsubcutaneously during about five days in a four or six week cycle in anamount ranging from about 1 to about 750 mg/m²/day, from about 25 toabout 500 mg/m²/day, from about 50 to about 250 mg/m²/day, or from about50 to about 200 mg/m²/day. In certain embodiments, GM-CSF may beadministered in an amount of from about 60 to about 500 mcg/m²intravenously over 2 hours or from about 5 to about 12 mcg/m²/daysubcutaneously. In certain embodiments, G-CSF may be administeredsubcutaneously in an amount of about 1 mcg/kg/day initially and can beadjusted depending on rise of total granulocyte counts. The maintenancedose of G-CSF may be administered in an amount of about 300 (in smallerpatients) or 480 mcg subcutaneously. In certain embodiments, EPO may beadministered subcutaneously in an amount of 10,000 Unit 3 times perweek.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with melphalan anddexamethasone to patients with amyloidosis. In certain embodiments, acompound provided herein, e.g., a compound provided herein, or anenantiomer or a mixture of enantiomers thereof, or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof, and steroids can be administered to patients with amyloidosis.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with gemcitabine andcisplatinum to patients with locally advanced or metastatic transitionalcell bladder cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination with asecond active ingredient as follows: temozolomide to pediatric patientswith relapsed or progressive brain tumors or recurrent neuroblastoma;celecoxib, etoposide and cyclophosphamide for relapsed or progressiveCNS cancer; temodar to patients with recurrent or progressivemeningioma, malignant meningioma, hemangiopericytoma, multiple brainmetastases, relapased brain tumors, or newly diagnosed glioblastomamultiforms; irinotecan to patients with recurrent glioblastoma;carboplatin to pediatric patients with brain stem glioma; procarbazineto pediatric patients with progressive malignant gliomas;cyclophosphamide to patients with poor prognosis malignant brain tumors,newly diagnosed or recurrent glioblastoma multiforms; Gliadel® for highgrade recurrent malignant gliomas; temozolomide and tamoxifen foranaplastic astrocytoma; or topotecan for gliomas, glioblastoma,anaplastic astrocytoma or anaplastic oligodendroglioma.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with methotrexate,cyclophosphamide, taxane, abraxane, lapatinib, herceptin, aromataseinhibitors, selective estrogen modulators, estrogen receptorantagonists, and/or PLX3397 (Plexxikon) to patients with metastaticbreast cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with temozolomide topatients with neuroendocrine tumors.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with gemcitabine topatients with recurrent or metastatic head or neck cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with gemcitabine topatients with pancreatic cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients with coloncancer in combination with ARISA®, avastatin, taxol, and/or taxotere.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with capecitabineand/or PLX4032 (Plexxikon) to patients with refractory colorectal canceror patients who fail first line therapy or have poor performance incolon or rectal adenocarcinoma.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withfluorouracil, leucovorin, and irinotecan to patients with Dukes C & Dcolorectal cancer or to patients who have been previously treated formetastatic colorectal cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withrefractory colorectal cancer in combination with capecitabine, xeloda,and/or CPT-11.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with capecitabine andirinotecan to patients with refractory colorectal cancer or to patientswith unresectable or metastatic colorectal carcinoma.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered alone or in combinationwith interferon alpha or capecitabine to patients with unresectable ormetastatic hepatocellular carcinoma; or with cisplatin and thiotepa topatients with primary or metastatic liver cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withpegylated interferon alpha to patients with Kaposi's sarcoma.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withfludarabine, carboplatin, and/or topotecan to patients with refractoryor relapsed or high-risk acuted myelogenous leukemia.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withliposomal daunorubicin, topotecan and/or cytarabine to patients withunfavorable karotype acute myeloblastic leukemia.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withgemcitabine, abraxane, erlotinib, geftinib, and/or irinotecan topatients with non-small cell lung cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withcarboplatin and irinotecan to patients with non-small cell lung cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered with doxetaxol topatients with non-small cell lung cancer who have been previouslytreated with carbo/VP 16 and radiotherapy.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withcarboplatin and/or taxotere, or in combination with carboplatin,pacilitaxel and/or thoracic radiotherapy to patients with non-small celllung cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withtaxotere to patients with stage IIIB or IV non-small cell lung cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withoblimersen (Genasense®) to patients with small cell lung cancer.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withABT-737 (Abbott Laboratories) and/or obatoclax (GX15-070) to patientswith lymphoma and other blood cancers.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered alone or in combinationwith a second active ingredient such as vinblastine or fludarabine topatients with various types of lymphoma, including, but not limited to,Hodgkin's lymphoma, non-Hodgkin's lymphoma, cutaneous T-Cell lymphoma,cutaneous B-Cell lymphoma, diffuse large B-Cell lymphoma or relapsed orrefractory low grade follicular lymphoma.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered in combination withtaxotere, IL-2, IFN, GM-CSF, PLX4032 (Plexxikon) and/or dacarbazine topatients with various types or stages of melanoma.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered alone or in combinationwith vinorelbine to patients with malignant mesothelioma, or stage IIIBnon-small cell lung cancer with pleural implants or malignant pleuraleffusion mesothelioma syndrome.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withvarious types or stages of multiple myeloma in combination withdexamethasone, zoledronic acid, palmitronate, GM-CSF, biaxin,vinblastine, melphalan, busulphan, cyclophosphamide, IFN, palmidronate,prednisone, bisphosphonate, celecoxib, arsenic trioxide, PEG INTRON-A,vincristine, or a combination thereof.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withrelapsed or refractory multiple myeloma in combination with doxorubicin(Doxil®), vincristine and/or dexamethasone (Decadron®).

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withvarious types or stages of ovarian cancer such as peritoneal carcinoma,papillary serous carcinoma, refractory ovarian cancer or recurrentovarian cancer, in combination with taxol, carboplatin, doxorubicin,gemcitabine, cisplatin, xeloda, paclitaxel, dexamethasone, or acombination thereof.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withvarious types or stages of prostate cancer, in combination with xeloda,5 FU/LV, gemcitabine, irinotecan plus gemcitabine, cyclophosphamide,vincristine, dexamethasone, GM-CSF, celecoxib, taxotere, ganciclovir,paclitaxel, adriamycin, docetaxel, estramustine, Emcyt, denderon or acombination thereof.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withvarious types or stages of renal cell cancer, in combination withcapecitabine, IFN, tamoxifen, IL-2, GM-CSF, Celebrex®, or a combinationthereof.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withvarious types or stages of gynecologic, uterus or soft tissue sarcomacancer in combination with IFN, a COX-2 inhibitor such as Celebrex®,and/or sulindac.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withvarious types or stages of solid tumors in combination with celebrex,etoposide, cyclophosphamide, docetaxel, apecitabine, IFN, tamoxifen,IL-2, GM-CSF, or a combination thereof.

In certain embodiments, a compound provided herein, e.g., a compoundprovided herein, or an enantiomer or a mixture of enantiomers thereof,or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withscleroderma or cutaneous vasculitis in combination with celebrex,etoposide, cyclophosphamide, docetaxel, apecitabine, IFN, tamoxifen,IL-2, GM-CSF, or a combination thereof.

Also encompassed herein is a method of increasing the dosage of ananti-cancer drug or agent that can be safely and effectivelyadministered to a patient, which comprises administering to the patient(e.g., a human) or an enantiomer or a mixture of enantiomers thereof, ora pharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof. Patients that can benefit by thismethod are those likely to suffer from an adverse effect associated withanti-cancer drugs for treating a specific cancer of the skin,subcutaneous tissue, lymph nodes, brain, lung, liver, bone, intestine,colon, heart, pancreas, adrenal, kidney, prostate, breast, colorectal,or combinations thereof. The administration of a compound providedherein, e.g., a compound provided herein, or an enantiomer or a mixtureof enantiomers thereof, or a pharmaceutically acceptable salt, solvate,hydrate, co-crystal, clathrate, or polymorph thereof, alleviates orreduces adverse effects which are of such severity that it wouldotherwise limit the amount of anti-cancer drug.

In one embodiment, a compound provided herein, e.g., a compound providedherein, or an enantiomer or a mixture of enantiomers thereof, or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered orally and daily in anamount ranging from about 0.1 to about 150 mg, from about 1 to about 50mg, or from about 2 to about 25 mg, prior to, during, or after theoccurrence of the adverse effect associated with the administration ofan anti-cancer drug to a patient. In certain embodiments, a compoundprovided herein, e.g., a compound provided herein, or an enantiomer or amixture of enantiomers thereof, or a pharmaceutically acceptable salt,solvate, hydrate, co-crystal, clathrate, or polymorph thereof, isadministered in combination with specific agents such as heparin,aspirin, coumadin, or G-CSF to avoid adverse effects that are associatedwith anti-cancer drugs such as but not limited to neutropenia orthrombocytopenia.

In one embodiment, a compound provided herein, e.g., a compound providedherein, or an enantiomer or a mixture of enantiomers thereof, or apharmaceutically acceptable salt, solvate, hydrate, co-crystal,clathrate, or polymorph thereof, is administered to patients withdiseases and disorders associated with or characterized by, undesiredangiogenesis in combination with additional active ingredients,including, but not limited to, anti-cancer drugs, anti-inflammatories,antihistamines, antibiotics, and steroids.

In another embodiment, encompassed herein is a method of treating,preventing and/or managing cancer, which comprises administering acompound provided herein, or an enantiomer or a mixture of enantiomersthereof, or a pharmaceutically acceptable salt, solvate, hydrate,co-crystal, clathrate, or polymorph thereof, in conjunction with (e.g.before, during, or after) conventional therapy including, but notlimited to, surgery, immunotherapy, biological therapy, radiationtherapy, or other non-drug based therapy presently used to treat,prevent or manage cancer. The combined use of the compound providedherein and conventional therapy may provide a unique treatment regimenthat is unexpectedly effective in certain patients. Without beinglimited by theory, it is believed that a compound provided herein mayprovide additive or synergistic effects when given concurrently withconventional therapy. In certain embodiments provided herein is acompound provided herein for use in a method of treating, preventingand/or managing cancer, wherein the method comprises the above definedadministration step.

As discussed elsewhere herein, encompassed herein is a method ofreducing, treating and/or preventing adverse or undesired effectsassociated with conventional therapy including, but not limited to,surgery, chemotherapy, radiation therapy, hormonal therapy, biologicaltherapy and immunotherapy. Also encompassed herein is a compoundprovided herein for use in a method of reducing, treating and/orpreventing adverse or undesired effects associated with conventionaltherapy including, but not limited to, surgery, chemotherapy, radiationtherapy, hormonal therapy, biological therapy and immunotherapy. Acompound provided herein, e.g., a compound provided herein, or anenantiomer or a mixture of enantiomers thereof, or a pharmaceuticallyacceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorphthereof, and other active ingredient can be administered to a patientprior to, during, or after the occurrence of the adverse effectassociated with conventional therapy.

In one embodiment, a compound provided herein can be administered in anamount ranging from about 0.1 to about 150 mg, from about 1 to about 25mg, or from about 2 to about 10 mg orally and daily alone, or incombination with a second active agent disclosed herein (see, e.g.,section 5.4), prior to, during, or after the use of conventionaltherapy.

The following examples are offered by way of illustration, and not byway of limitation.

6. EXAMPLES 6.1 Preparation of3-(4-amino-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dione(lenalidomide) Methyl 2-bromomethyl-3-nitrobenzoate

A stirred mixture of methyl 2-methyl-3-nitrobenzoate (14.0 g, 71.7 mmol)and N-bromosuccinimide (15.3 g, 86.1 mmol) in carbon tetrachloride (200mL) was heated under gentle reflux for 15 hours while a 100 W bulbsituated 2 cm away was shining on the flask. The mixture was filteredand the solid was washed with methylene chloride (50 mL). The filtratewas washed with water (2×100 mL), brine (100 mL) and dried. The solventwas removed in vacuo and the residue was purified by flashchromatography (hexane/ethyl acetate, 8/2) to afford 19 g (96%) of theproduct as a yellow solid: mp 70.0-71.5° C.; 1H NMR (CDCl₃) δ 8.12-8.09(dd, J=1.3 and 7.8 Hz, 1H), 7.97-7.94 (dd, J=1.3 and 8.2 Hz, 1H), 7.54(t, J=8.0 Hz, 1H). 5.15 (s, 2H), 4.00 (s, 3H); ¹³C NMR (CDCl₃) δ 165.85,150.58, 134.68, 132.38, 129.08, 127.80, 53.06, 22.69; HPLC, WaterNove-Pak/C18, 3.9×150 mm, 4 micron, 1 mL/min, 240 nm, 40/60 CH₃CN/0.1%H₃PO₄(aq) 7.27 min(98.92%); Anal. Calcd for C₉H₈NO₄Br: C, 39.44; H,2.94; N, 5.1 1; Br, 29.15. Found: C, 39.46; H, 3.00; N, 5.00; Br, 29.11.

t-Butyl N-(1-oxo-4-nitroisoindolin-2-yl)-L-glutamine

Triethylamine (2.9 g, 28.6 mmol) was added dropwise to a stirred mixtureof methyl 2-bromomethyl-3-nitrobenzoate (3.5 g, 13.0 mmol) andL-glutamine t-butyl ester hydrochloride (3.1 g, 13.0 mmol) intetrahydrofuran (90 mL). The mixture was heated to reflux for 24 hours.To the cooled mixture was added methylene chloride (150 mL) and themixture was washed with water (2×40 mL), brine (40 mL) and dried. Thesolvent was removed in vacuo and the residue was purified by flashchromatography (3% CH₃OH in methylene chloride) to afford 2.84 g (60%)of crude product which was used directly in the next reaction: 1H NMR(CDCl₃) δ 8.40 (d, J=8.1 Hz, 1H), 8.15 (d, J=7.5 Hz, 1H), 7.71 (t, J=7.8Hz, 1H), 5.83 (s, 1H), 5.61 (s, 1H), 5.12 (d, J=19.4 Hz, 1H), 5.04-4.98(m, 1H), 4.92 (d, J=19.4 Hz, 1H), 2.49-2.22 (m, 4H). 1.46 (s, 9H); HPLC,Waters Nova-Pak C18, 3.9×150 mm, 4 micron, 1 mL/min, 240 nm, 25/75CH₃CN/0.1% H₃PO₄(aq) 6.75 min(99.94%).

N-(1-oxo-4-nitroisoindolin-2-yl)-L-glutamine

Hydrogen chloride gas was bubbled into a stirred 5° C. solution oft-butyl N-(1-oxo-4-nitro-isoindolin-2-yl)-L-glutamine (3.6 g, 9.9 mmol)in methylene chloride (60 mL) for 1 hour. The mixture was then stirredat room temperature for another hour. Ether (40 mL) was added and theresulting mixture was stirred for 30 minutes. The slurry was filtered,washed with ether and dried to afford 3.3 g of the product: 1H NMR(DMSO-d₆) δ 8.45 (d, J=8.1 Hz, 1H), 8.15 (d, J=7.5 Hz, 1H), 7.83 (t,J=7.9 Hz. 1H), 7.24 (s, 1H), 6.76 (s, 1H), 4.93 (s, 2H), 4.84-4.78 (dd,J=4.8 amd 10.4 Hz, 1H), 2.34-2.10 (m, 4H); ¹³C NMR (DMSO-d₆) δ 173.03,171.88, 165.96, 143.35, 137.49, 134.77, 130.10, 129.61, 126.95, 53.65,48.13, 31.50, 24.69; Anal. Calcd for C₁₃H₁₃N₃O₆: C, 50.82; H, 4.26; N,13.68. Found: C, 50.53; H. 4.37; N, 13.22.

(S)-3-(1-oxo-4-nitroisoindolin-2-yl)piperidine-2,6-dione

A stirred suspension mixture ofN-(1-oxo-4-nitroisoindolin-2-yl)-L-glutamine (3.2 g, 10.5 mmol) inanhydrous methylene chloride (150 mL) was cooled to −40° C. withisopropanol/dry ice bath. Thionyl chloride (0.82 mL, 11.3 mmol) wasadded dropwise to the cooled mixture followed by pyridine (0.9 g. 1 1.3mmol). After 30 min, triethylamine (1.2 g, 11.5 mmol) was added and themixture was stirred at −30 to −40° C. for 3 hours. The mixture waspoured into ice water (200 mL) and the aqueous layer was extracted withmethylene chloride (40 mL). The methylene chloride solution was washedwith water (2×60 mL), brine (60 mL) and dried. The solvent was removedin vacuo and the solid residue was slurried with ethyl acetate (20 mL)to give 2.2 g (75%) of the product as a white solid: mp 285° C.; 1H NMR(DMSO-d₆) δ: 1.04 (s, 1H), 8.49-8.45 (dd, J=0.8 and 8.2 Hz, 1H),8.21-8.17 (dd, J=7.3 Hz, 1H), 7.84 (t, J=7.6 Hz, 1H), 5.23-5.15 (dd,J=4.9 and 13.0 Hz, 1H), 4.96 (dd, J=19.3 and 32.4 Hz, 2H), 3.00-2.85 (m,1H), 2.64-2.49 (m, 2H), 2.08-1.98 (m, 1H); ¹³C NMR (DMSO-d₆) δ 172.79,170.69, 165.93, 143.33, 137.40, 134.68, 130.15, 129.60, 127.02, 51.82,48.43, 31.16. 22.23; HPLC, Waters Nove-Pak/C18, 3.9×150 mm, 4 micron, 1mL/min, 240 nm, 20/80 CH₃CN/0.1% H₃PO₄(aq) 3.67 min(100%); Anal. Calcdfor C₁₃H_(n)N₃O₅: C, 53.98; H, 3.83; N, 14.53. Found: C, 53.92; H, 3.70;N, 14.10.

3-(4-amino-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dione

A mixture of (S)-3-(1-oxo-4-nitroisoindolin-2-yl)piperidine-2,6-dione(1.0 g, 3.5 mmol) and 10% Pd/C (0.3 g) in methanol (600 mL) washydrogenated in a Parr-Shaker apparatus at 50 psi of hydrogen for 5hours. The mixture was filtered through Celite and the filtrate wasconcentrated in vacuo. The solid was slurried in hot ethyl acetate for30 min, filtered and dried to afford 0.46 g (51%) of the product as awhite solid: mp 235.5-239° C.; ¹H NMR (DMSO-d₆) δ 11.01 (s, 1H). 7.19(t, J=7.6 Hz, 1H). 6.90 (d. J=7.3 Hz, 1H), 6.78 (d, J=7.8 Hz, 1H), 5.42(s, 2H). 5.12 (dd. J=5.1 and 13.1 Hz, 1H), 4.17 (dd, J=17.0 and 28.8 Hz,2H), 2.92-2.85 (m, 1H). 2.64-2.49 (m, 1H). 2.34-2.27 (m, 1H), 2.06-1.99(m, 1H); ¹³C NMR (DMSO-d₆) δ 172.85, 171.19, 168.84, 143.58, 132.22.128.79, 125.56, 1 16.37, 1 10.39, 51.48, 45.49, 31.20, 22.74; HPLC.Waters Nova-Pak/C18, 3.9×150 mm, 4 micron, 1 mL/min, 240 nm, 10/90CH₃CN/0.1% H₃PO₄(aq) 0.96 min(100%); Chiral analysis, Daicel Chiral PakAD, 40/60 Hexane/IPA, 6.60 min(99.42%); Anal. Calcd for C₁₃H₁₃N₃O₃: C,60.23; H, 5.05; N, 16.21. Found: C, 59.96; H. 4.98; N, 15.84.

3-(4-Amino-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dione mayalso be prepared by methods known in the art, for example, as providedin Drugs of the Future, 2003, 28(5): 425-431, the entirety of which isincorporated by reference.

6.2 Preparation of3-(5-amino-2-methyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione(Compound A)

To a solution of potassium hydroxide (16.1 g, 286 mmol) in water (500mL), was added 3-nitrophthalimide (25.0 g, 130 mmol) in portion at 0° C.The suspension was stirred at 0° C. for 3 hrs, and then heated to 30° C.for 3 hrs. To the solution, was added HCl (100 mL, 6N). The resultingsuspension was cooled to 0° C. for 1 hr. The suspension was filtered andwashed with cold water (2×10 mL) to give 3-nitro-phthalamic acid as awhite solid (24.6 g, 90% yield): ¹H NMR (DMSO-d₆) δ 7.69 (brs, 1H, NHH),7.74 (t, J=8 Hz, 1H, Ar), 7.92 (dd, J=1, 8 Hz, 1H, Ar), 8.13 (dd, J=1, 8Hz, 1H, Ar), 8.15 (brs, 1H, NHH), 13.59 (s, 1H, OH); ¹³C NMR (DMSO-d₆) δ125.33, 129.15, 130.25, 132.54, 136.72, 147.03, 165.90, 167.31.

To a mixture of 3-nitro-phthalamic acid (24.6 g, 117 mmol) and potassiumhydroxide (6.56 g, 117 mmol) in water (118 mL), was added a mixture ofbromine (6 mL), potassium hydroxide (13.2 g, 234 mmol) in water (240 mL)at 0° C., followed by addition of a solution of potassium hydroxide(19.8 g, 351 mmol) in water (350 mL). After 5 minutes at 0° C., themixture was heated in a 100° C. oil bath for 1 hr. The reaction solutionwas cooled to room temperature, and then, in an ice-water bath for 30minutes. To the mixture, a solution of HCl (240 mL, 2N) was addeddropwise at 0° C., and the resulting mixture was kept for 1 hr. Thesuspension was filtered and washed with water (5 mL) to give2-amino-6-nitro-benzoic acid as yellow solid (15.6 g, 73% yield): HPLC:Waters Symmetry C18, 5 μm, 3.9×150 mm, 1 mL/min, 240 nm, CH₃CN/0.1%H₃PO₄, 5% grad to 95% over 5 min, 5.83 min (85%); ¹H NMR (DMSO-d₆) δ6.90 (dd, J=1, 8 Hz, 1H, Ar), 7.01 (dd, J=1, 9 Hz, 1H, Ar), 7.31 (t, J=8Hz, 1H, Ar), 8.5-9.5 (brs, 3H, OH, NH₂); ¹³C NMR (DMSO-d₆) δ 105.58,110.14, 120.07, 131.74, 149.80, 151.36, 166.30; LCMS: MH=183.

A mixture of 2-amino-6-nitro-benzoic acid (1.5 g, 8.2 mmol) in aceticanhydride (15 mL) was heated at 200° C. for 30 minutes in a microwaveoven. The mixture was filtered and washed with ethyl acetate (20 mL).The filtrate was concentrated in vacuo. The solid was stirred in ether(20 mL) for 2 hrs. The suspension was filtered and washed with ether (20mL) to give 2-methyl-5-nitro-benzo[d][1,3]oxazin-4-one as a light brownsolid (1.4 g, 85% yield): HPLC: Waters Symmetry C₁₈, 5 μm, 3.9×150 mm, 1mL/min, 240 nm, CH₃CN/0.1% H₃PO₄, 5% grad 95% in 5 min, 5.36 min (92%);¹H NMR (DMSO-d₆) δ 2.42 (s, 3H, CH₃), 7.79 (dd, J=1, 8 Hz, 1H, Ar), 7.93(dd, J=1, 8 Hz, 1H, Ar), 8.06 (t, J=8 Hz, 1H, Ar); ¹³C NMR (DMSO-d₆) δ20.87, 107.79, 121.54, 128.87, 137.19, 147.12, 148.46, 155.18, 161.78;LCMS: MH=207.

Two vials each with a suspension of5-nitro-2-methyl-benzo[d][1,3]oxazin-4-one (0.60 g, 2.91 mmol) and3-amino-piperidine-2,6-dione hydrogen chloride (0.48 g, 2.91 mmol) inpyridine (15 mL) were heated at 170° C. for 10 minutes in a microwaveoven. The suspension was filtered and washed with pyridine (5 mL). Thefiltrate was concentrated in vacuo. The resulting mixture was stirred inHCl (30 mL, 1N), ethyl acetate (15 mL) and ether (15 mL) for 2 hrs. Thesuspension was filtered and washed with water (30 mL) and ethyl acetate(30 mL) to give a dark brown solid, which was stirred with methanol (50mL) at room temperature overnight. The suspension was filtered andwashed with methanol to give3-(2-methyl-5-nitro-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione as ablack solid (490 mg, 27% yield). The solid was used in the next stepwithout further purification.

A mixture of3-(2-methyl-5-nitro-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione (250mg) and Pd(OH)₂ on carbon (110 mg) in DMF (40 mL) was shaken underhydrogen (50 psi) for 12 hrs. The suspension was filtered through a padof Celite and washed with DMF (10 mL). The filtrate was concentrated invacuo and the resulting oil was purified by flash column chromatography(silica gel, methanol/methylene chloride) to give3-(5-amino-2-methyl-4-oxo-4H-quinazolin-3-yl)-piperidine-2,6-dione as awhite solid (156 mg, 69% yield): HPLC: Waters Symmetry C₁₈, 5 μm,3.9×150 mm, 1 mL/min, 240 nm, 10/90 CH₃CN/0.1% H₃PO₄, 3.52 min (99.9%);mp: 293-295° C.; ¹H NMR (DMSO-d₆) δ 2.10-2.17 (m, 1H, CHH), 2.53 (s, 3H,CH₃), 2.59-2.69 (m, 2H, CH₂), 2.76-2.89 (m, 1H, CHH), 5.14 (dd, J=6, 11Hz, 1H, NCH), 6.56 (d, J=8 Hz, 1H, Ar), 6.59 (d, J=8 Hz, 1H, Ar), 7.02(s, 2H, NH₂), 7.36 (t, J=8 Hz, 1H, Ar), 10.98 (s, 1H, NH); ¹³C NMR(DMSO-d₆) δ 20.98, 23.14, 30.52, 55.92, 104.15, 110.48, 111.37, 134.92,148.17, 150.55, 153.62, 162.59, 169.65, 172.57; LCMS: MH=287; Anal.Calcd. for C₁₄H₁₄N₄O₃+0.3 H₂O: C, 57.65; H, 5.05; N, 19.21. Found: C,57.50; H, 4.73; N, 19.00.

6.3 Unbound CRBN Crystal Structure

This example describes the preparation of a CRBN crystal. CereblonIMiD®-binding domain can be purified as follows: The gene encoding thethalidomide binding domain (TBD) of human CRBN (amino acids 319-427 (SEQID NO: 5)) or mouse CRBN (amino acids 322-430 (SEQ ID NO: 6)) is codonoptimized and inserted into a pGEX6P-3 vector for expression as aGST-fusion protein in E. coli. BL21 (DE3) Star cells transformed witheither plasmid are grown to OD 0.6 in TB media supplemented with 50 μMzinc acetate, and induced with 0.5 mM IPTG for 4 hours at 37 C. Cellsare resuspended in lysis buffer containing 50 mM Tris pH 7, 150 mM NaCl,10% glycerol, 2 mM TECP, 1 mM DTT, 100 U/mL benzonase (Novagen), 1×Protease Inhibitor Cocktail-EDTA free (SD Biosciences), 0.5 mg/mLlysozyme (Sigma), and sonicated for 30 s before ultracentrifuation for30 min at 100,000×g. GST-fused CRBN is then bound to glutathioneaffinity resin, washed in 50 mM Tris pH 7, 150 mM NaCl, 10% glycerol, 2mM TCEP, 1 mM DTT, and eluted in the same buffer with the addition of 40mM reduced glutathione. The GST tag is removed by overnight cleavage at4 C with PreScission™ Protease (1 U/mg protein, GE Healthcare). CRBN TBDis further purified with ion-exchange chromatography by diluting thecleaved protein to 75 mM NaCl using 50 mM Tris pH 7, 2 mM TCEP and 1 mMDTT, and binding to either a Mono S column (mouse TBD) or heparin column(human TBD). Protein is eluted using a gradient from 90 mM to 1M NaCland pooled for size exclusion chromatography. Mouse CRBN TBD can bepurified by size exclusion over an S75 16/600 in 5 mM sodium acetate pH6, 10 mM TECP, and 5 mM DTT. Human CRBN TBD can be purified over an S7516/600 in 20 mM MES pH 6, 200 mM NaCl, 10 mM TCEP and 1 mM DTT. Eitherthe human or the mouse protein can be concentrated to 17 mg/mL.Alternatively, residues of murine 321-429 (SEQ ID NO: 7) fused to GSTcan be expressed in E. coli. Cells are lysed by sonication and thesoluble fraction purified using GST-trap, ion exchange andsize-exclusion chromatography. Protein can be concentrated to 28 mg/mlin 50 mM acetate buffer, pH 6.0, 1 mM DTT, 10 mM TCEP. Crystals can beobtained by sitting drop vapor diffusion by mixing the protein buffer1:1 with and equilibrating against a mother liquor of crystallizationbuffer. For the mouse unbound TBD, the crystallization buffer contains100 mM Sodium acetate pH 5, 600-800 mM Ammonium sulfate. Crystals can begrown at 4 degrees centrigrade and cryoprotected by addition of 20%glycerol and frozen under liquid nitrogen.

6.4 CRBN-Drug Complex Crystal Structures

This example describes the preparation of a crystal of CRBN complexedwith a second compound used to study structure-activity relationships.

A crystal of CRBN complexed with a Apo was prepared and used as anegative control. In addition, a crystal of CRBN complexed withthalidomide, pomalidomide, CC-220, or CC-885 was prepared.

FIG. 2 depicts identical projections of certain CMA binding surfaces ofCRBN and shows protein conformational changes.

FIG. 3A depicts the crystal structure of CRBN prior to CC-220 binding,and FIG. 3B depicts the crystal structure of CC-220 in CRBN, in whichthe drug can act as a “molecular glue” or bridge with a substrate, suchas a CRBN-associated protein.

FIG. 4 depicts a complex of CRBN and CC-220 or thalidomide. A 50°rotation of “pthalimide” ring in CC-220 relative to thalidomide orpomalidomide is observed. Such a rotation can allows for differentbiological effects downstream, as well as the resulting therapeuticeffects.

6.5 Aiolos Degradation Assay for Identification of CMAs

The example describes an exemplary method for assaying a CRBN-mediatedbiological activity, and specifically Aiolos degradation.

Immunohistochemistry is performed using standard methods. For example,Immunohistochemistry is performed on the Bond-Max® automated slidestainer (Leica Microsystems) using the associated Bond Polymer Refine®Detection Kit. Four micron thick FFPE sections are deparaffinized on theinstrument. Antigen retrieval is performed with Epitope Retrieval™ 2 (pH9.0) for 20 minutes at 100° C. The slides are blocked for endogenousperoxidase activity with Peroxide Block for 5 minutes at roomtemperature. Sections are then incubated with rabbit polyclonal antibodyto Aiolos (Santa Cruz, sc-101982) at a 1/1000 dilution for 15 minutes atroom temperature, followed by incubation with HRP labeled Polymer for 8minutes at room temperature. Enzymatic detection of anti-Aiolos antibodyis accomplished with hydrogen peroxide substrate and diaminobenzidinetetrahydrochloride (DAB) chromogen at room temperature for 10 minutes.Slides are counterstained with Hematoxylin for 5 minutes at roomtemperature.

6.6 Production of CC-885 Analogs

This example describes the production of CC-885, and analogs thereof.

1-(3-Chloro-4-methyl-phenyl)-3-[2-(2,6-dioxo-piperidin-3-yl)-1-oxo-2,3-dihydro-1H-isoindol-5-ylmethyl]-urea

Step 1

A mechanically stirred mixture of 4-bromo-2-methyl-benzoic acid (100 g,465 mmol), iodomethane (95 g, 670 mmol) and sodium bicarbonate (112 g,1340 mmol) in DMF (325 mL) was heated at 80° C. overnight. The reactionmixture was cooled to room temperature and partitioned between water(1500 mL) and 4:1 hexanes:ethyl acetate (1500 mL). The organic layer waswashed with water and dried (Na₂SO₄). The solvent was removed undervacuum to give 110 g of 4-bromo-2-methyl-benzoic acid methyl ester as anoil, in 100% yield; ¹H NMR (DMSO-d₆) δ 2.51 (s, 3H), 3.84 (s, 3H),7.40-7.78 (m, 3H).

Step 2

A mechanically stirred mixture of 4-bromo-2-methyl-benzoic acid methylester (115 g, 500 mmol), N-bromosuccinimide (90 g, 500 mmol) and AIBN(3.1 g) in acetonitrile (700 mL) was warmed over 45 minutes to a gentlereflux, and held at reflux for 21 hours. The reaction mixture was cooledto room temperature, diluted with saturated aqueous sodium bisulfite,and concentrated in vacuo. The residue was partitioned between water and1:1 hexanes:ethyl acetate. The organic phase was washed with water,brine, and filtered through a pad of silica gel. The solvent was removedunder vacuum to give an oil/solid mixture, which was digested in etherand filtered. The filtrate was chromatographed on silica gel using ahexanes-ethyl acetate gradient, eluting the product at 4:1 hexanes-ethylacetate and providing 102 g of 4-bromo-2-bromomethyl-benzoic acid methylester, in 66% yield; ¹H NMR (DMSO-d₆) δ 3.87 (s, 3H), 4.99 (s, 2H),7.67-7.97 (m, 3H).

Step 3

A mechanically stirred mixture of 4-bromo-2-bromomethyl-benzoic acidmethyl ester (121 g, 390 mmol) and 3-amino-piperidine-2,6-dionehydrochloride (64.2 g, 390 mmol) in DMF (400 mL) was treated dropwisewith triethylamine (98.5 g, 980 mmol) over 75 minutes. After theaddition was completed, the reaction mixture was stirred at roomtemperature overnight. The mixture was quenched sequentially with aceticacid (50 mL), water (2500 mL) and a 1:1 mixture of ethyl acetate andhexanes (600 mL). After stirring the mixture for 20 minutes, the solidwas filtered, washed with water and air dried overnight. The solid wasstirred in acetic acid (200 mL) and refluxed for 2 hours. The mixturewas cooled to room temperature and filtered. The solid was washed withadditional acetic acid, hexanes and air dried overnight to give 25.4 gof 3-(5-bromo-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dione as agrey solid, in 20% yield; ¹H NMR (DMSO-d₆) δ 1.97-2.04 (m, 1H),2.32-2.46 (m, 1H), 2.56-2.63 (m, 1H), 2.85-2.97 (m, 1H), 4.34 (d, J=17.7Hz, 1H), 4.47 (d, J=17.7 Hz, 1H), 5.11 (dd, J=13.2 Hz, J=5.1 Hz, 1H),7.67 (d, J=8.1 Hz, 1H), 7.72 (dd, J=8.1 Hz, J=1.5 Hz, 1H), 7.89 (d,J=0.9 Hz, 1H), 11.00 (s, 1H).

Step 4

A mechanically stirred mixture of3-(5-bromo-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dione (25.2g, 78 mmol), bis(diphenylphosphino)ferrocene (2.0 g),tris(dibenzylideneacetone)dipalladium (2.0 g) and zinc cyanide (9.4 g,80 mmol) in DMF (300 mL) was heated to 120° C. and stirred at thistemperature for 19 hours. The reaction mixture was cooled to 40° C., andanother 9.4 g of zinc cyanide, 2 g of bis(diphenylphosphino)ferroceneand 2 g of tris(dibenzylideneacetone)dipalladium were added. The mixturewas stirred at 120° C. for 2 hours, cooled to room temperature andquenched with water (900 mL). The solid was filtered, washed withadditional water and air dried overnight. The solid was stirred in hotacetic acid (200 mL) for 20 minutes. The solid was filtered, washed withadditional acetic acid, ethyl acetate and hexanes, and air dried to give30.8 g of crude2-(2,6-dioxo-piperidin-3-yl)-1-oxo-2,3-dihydro-1H-isoindole-5-carbonitrileas a gray solid; ¹H NMR (DMSO-d₆) δ 1.99-2.06 (m, 1H), 2.35-2.45 (m,1H), 2.57-2.63 (m, 1H), 2.86-2.98 (m, 1H), 4.42 (d, J=17.7 Hz, 1H), 4.55(d, J=17.7 Hz, 1H), 5.15 (dd, J=13.2 Hz, J=5.1 Hz, 1H), 7.91 (d, J=7.8Hz, 1H), 7.99 (dd, J=7.8 Hz, J=0.9 Hz, 1H), 8.16 (s, 1H), 11.03 (s, 1H).

Step 5

A mixture of2-(2,6-dioxo-piperidin-3-yl)-1-oxo-2,3-dihydro-1H-isoindole-5-carbonitrile(9.2 g, 34 mmol), 10% Pd—C (1.7 g) and concentrated HCl (5.3 g) inN-methylpyrrolidone (300 mL) was hydrogenated at 58 psi overnight. Thecrude reaction mixture was filtered through Celite, and the catalystwashed with water. The combined filtrate was concentrated in vacuo, andthe product,3-(5-aminomethyl-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dionehydrochloride, was isolated by fractional crystallization of the residuefrom isopropanol-water (1.9 g, 18%); ¹H NMR (DMSO-d₆) δ 1.85-2.20 (m,1H), 2.35-2.45 (m, 1H), 2.58-2.80 (m, 1H), 2.87-2.99 (m, 1H), 4.16 (s,2H), 4.35 (d, J=17.5 Hz, 1H), 4.49 (d, J=17.5 Hz, 1H), 5.13 (dd, J=13.2Hz, J=4.8 Hz, 1H), 7.63 (d, J=7.8 Hz, 1H), 7.72 (s, 1H), 7.79 (d, J=7.8Hz, 1H), 8.43 (br, 3H), 11.01 (s, 1H).

Step 6

A mixture of3-(5-aminomethyl-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-2,6-dionehydrochloride (0.50 g, 1.6 mmol), 3-chloro-4-methylphenyl isocyanate(0.27 g, 1.6 mmol) and TEA (0.32 g, 3.2 mmol) in THF (25 mL) was heatedto 40° C. with stirring under N₂. After 3 hours, an additional portionof 3-chloro-4-methylisocyanate (0.17 g, 1.1 mmol) was added, andstirring proceeded for 2 hours. The mixture was filtered, and the filterwas washed with ethyl acetate. The solid was triturated with 10 mL of1:1 acetone-DMF and filtered. The filter was washed with acetone, andthe solid was dried under vacuum, providing 430 mg of the product, in60% yield; mp 258-260° C.; HPLC, Waters Symmetry C-18, 3.9×150 mm, 5 am,1 mL/min, 240 nm, 40/60 CH₃CN/0.1% H₃PO₄, 4.49 (98.75%); ¹H NMR(DMSO-d₆) δ 1.90-1.96 (m, 1H), 2.16 (s, 3H), 2.25-2.39 (m, 1H),2.50-2.55 (m, 1H), 2.78-2.91 (m, 1H), 4.24 (d, J=18.0 Hz, 1H), 4.33-4.41(m, 3H), 5.04 (dd, J=13.5 Hz, J=4.5 Hz, 1H), 6.73 (t, J=6.0 Hz, 1H),7.04-7.13 (m, 2H), 7.36-7.44 (m, 2H), 7.59-7.44 (m, 2H), 8.69 (s, 1H),10.92 (s, 1H); ¹³C NMR (DMSO-d₆) δ 18.7, 22.5, 31.2, 42.8, 47.1, 51.5,116.4, 117.6, 121.9, 122.9, 126.9, 127.4, 130.3, 131.0, 133.0, 139.6,142.4, 144.7, 155.1, 167.9, 171.0, 172.9; Anal. Calcd for C₂₂H₂₁ClN₄O₄:C, 59.93; H, 4.80; N, 12.71. Found: C, 59.77; H, 4.61; N, 12.69.

6.7 CRBN is Required for the Anti-Proliferative Effect of CC-885 inHematological and Solid Tumors

Lenalidomide Competes with Compound A and CC-885 for CRBN

TMD8 (ABC) or Karpas 422 (GCB) cells were treated with eitherlenalidomide; Compound A; CC-122 and 100 μM lenalidomide,1-(3-chloro-4-methylphenyl)-3-((2-(2,6-dioxopiperidin-3-yl)-1-oxoisoindolin-5-yl)methyl)urea(CC-885); or CC-885 and 100 μM lenalidomide. Cells were cultured andcell-passaged long-term in lenalidomide or Compound A. The cells werethen analyzed for proliferation using a ³H-thymidine incorporationassay.

FIGS. 5A-5B show that lenalidomide competes with Compound A and CC-885for CRBN. FIG. 5A shows that co-treatment with Compound A and 10 μMlenalidomide blocks anti-proliferative effects of Compound A, thoughcompetition of binding to the CRBN complex. Likewise, FIG. 5B shows thatco-treatment with CC-885 and 10 μM lenalidomide blocksanti-proliferative effects of CC-885, though competition of binding tothe CRBN complex. Co-culture of Lenalidomide with either CC-122 orCC-885 dampens the activity of these compounds as they target the samebinding pocket with relative affinity.

6.8 Effect of CC-885 Analogs on CRBN Substrates

This example shows the effects of CC-885 analogs on CRBN substrates.

6.8.1. CC-885 Induces Early Apoptosis in the MM Cell Line H929

The multiple myeloma cell line, H929, was cultured and treated withCC-885 or other CMA analogs at various concentrations from 0.01 nM to1000 nM. Apoptosis was assessed at 24 hrs. later.

As shown in FIG. 6, CC-885 induced early apoptosis in the multiplemyeloma (MM) cell line H929, whereas other CMAs did not.

6.8.2. CC-885 is Potent Across a Panel of Solid Tumor Lines

The potency of CC-885 was assessed across a panel of tumor cell lines,including B-lymphoma, breast, CNS, colon, kidney, leukemia, lung,melanoma, multiple myeloma, ovary and prostate.

As shown in FIG. 7, CC-885 is potent across a panel of tumor lines.While there was a differential cytotoxicity across the cancer cellpanel, CC-885 had an overall low Therapeutic Index (i.e., toxic effectsat low doses). Of note, traditional IMiDs® have no activity in solidtumor cell lines.

6.8.3. CRBN is Required for Anti-Proliferative Activity of CC-885 in MMCells

Next, it was determined if CC-885 binds CRBN in U266 multiple myelomacells, and whether CRBN was required for CC-885 activity in those cells.

As shown in FIG. 8, CC-885 binds CRBN protein MM cell extracts.Immunoblot analysis of extracts prepared from U266 multiple myelomacells and pre-incubated with vehicle DMSO (D), Pomalidomide (Pom) orCC-885 at the indicated concentrations, and bound to thalidomide analogaffinity beads, washed and eluted with SDS buffer as previouslydescribed (Ito et al, 2010; Lopez-Girona et al, 2012). Samples weresubjected to SDS-PAGE and immunoblot analysis using anti-CRBN 65-76(1:10,000 dilution; Red signal) and anti-DDB1 (Cell Signaling) (1:2,000dilution; Green signal). A LI-COR Odissey system was used to quantifyCRBN band density and relative amounts of CRBN were determined byaveraging at least three DMSO controls and expressing CRBN in eachcompetition sample as percent inhibition of CRBN protein relative to theaveraged controls as 100% binding. Moreover, FIGS. 9 and 10 show thatCRBN is required for the anti-proliferative activity of CC-885 inmyeloma cells. FIG. 9 shows CRBN immunoblot of extracts from DF15, DF15Rshows lack of CRBN protein expression in DF15R cells. β-Tubulinimmunoblot used as loading control. Cell proliferation assay of DF15(sensitive), DF15R (resistant; CRBNnull) cells treated with a doseresponse of CC-885. Assays were done in triplicate and error barsrepresent s.d. Data for each cell line was normalized to treatment withvehicle (DMSO). FIG. 10 shows CRBN immunoblot of extracts from DF15,DF15R and DF15R cells re-expressing full length CRBN wild type (CRBNWT)or re-expressing RFP control. β-Tubulin immunoblot used as loadingcontrol. Cell proliferation assay of DF15 (sensitive), DF15R (resistant;CRBNnull), DF15R-hCRBNWT (human CRBN), DF15R-RFP cells treated with adose response of CC-885. Data shows that re-expression of human CRBN inDF15R cells recues CC-885 anti-proliferative activity. Assays were donein triplicate and error bars represent s.d. Data for each cell line wasnormalized to treatment with vehicle (DMSO).

6.8.4. CRBN is Required for Anti-Proliferative Activity in Breast CancerCells

Breast cancer cells (MDA-MB-231) were treated with CRBN siRNA or anegative control. CC-885 was added at a concentration between 0 to 100μM, and CRBN levels were assessed at 48 hours post treatment. CRBN wassignificantly reduced in treated cells, as compared to a negativecontrol receiving no siRNA (data not shown).

CC-885-mediated growth inhibition and pro-apoptotic activity were alsoassessed. As shown in FIG. 11, CRBN is required for both inhibition andpro-apoptotic activity of CC-885 in the MDA-MB-213 breast cancer cells.

6.9 Structural Basis for Differentiated Responsiveness toThalidomide-Class Drugs (IMiDs®) Defined by the Crystal Structure of aLenalidomide:Human Cereblon: DDB1 Complex

The ubiquitin-proteasome pathway (UPP) is the principal mechanism bywhich proteins become marked for degradation contributing tointracellular protein homeostasis. Dysregulation of this key proteinhomeostatic mechanism is implicated in the etiology of diseasesincluding cancer, neurological conditions and metabolic diseases(Petroski et al. BMC Biochem, 2008. 9Suppl1:S7. Drugs that modulate theubiquitin-proteasome pathway therefore have the potential to impact awide range of biological processes and diseases including cancer.Thalidomide (THAL) and related IMiD® immunomodulatory agents, such aslenalidomide (LEN) and pomalidomide (POM), have shown anticancer effectsin different indications by the direct inhibition of cancer cellproliferation, modulation of the tumor microenvironment, andimmunomodulation or stimulation (Ramsay et al., Blood, 2012.120(7):1412-21; Quach et al., Leukemia, 2010. 24(1):22-32; Ramsay etal., Blood, 2013. 121(14): p. 2704-14; Eve et al, Br J Haematol., 2012.159(2):154-63).

Cereblon (CRBN), first identified as a genetic cause of inheritedautosomal recessive mental retardation, is a component of a ubiquitin E3cullin4-ring ligase (CRL4) complex, and is the direct target of THAL andother IMiD® drugs. CRL4 ubiquitin ligases are formed by a Cullin protein(CUL4), which acts as an assembly factor that provides a scaffold forassembly of a RING-box domain protein (RBX1) and the adaptor proteinDamaged DNA Binding Protein 1 (DDB1) (Angers et al., Nature, 2006.443(7111):590-3). RBX1 is the docking site for the activated E2 protein,and DDB1 recruits substrate specificity receptors or DCAFs(DDB1-cullin4-associated-factors) to form the substrate-presenting sideof the CRL4 complex (Angers et al., Nature, 2006. 443(7111):590-3; He etal., Genes Dev, 2006. 20(21):2949-54; Higa et al. Nat Cell Biol, 2006.8(11): p. 1277-83). Roughly 60 DCAFs have been identified. These DCAFsare characterized by the presence of a WD-repeat domain (Higa et al. NatCell Biol, 2006. 8(11): 1277-83). Biochemical and genetic evidence hasshown that CRBN is a DCAF for CRL4 (Angers et al., Nature, 2006.443(7111):590-3, Ito et al., Science, 2010. 327(5971):1345-50), and thatbinding of IMiD® compounds to CRBN affects CRL4^(CRBN) ubiquitin E3ligase activity thus mediating the anti-proliferative effects onmultiple myeloma (MM) cells and the immunomodulatory effects on T cells(Ito et al., Science, 2010. 327(5971):1345-50; Lopez-Girona et al.,Leukemia, 2012. 26(11):2326-35; Zhu et al., Blood. 2011.118(18):4771-9).

Recently, several groups have identified the transcription factorsIkaros and Aiolos as substrates of the CRL4^(CRBN)-IMiD® drug complex,thus explaining many of the therapeutic effects of IMiD® compounds onimmune and tumor cells. These reports describe that binding of IMiD®compounds to CRBN promotes recruitment of Ikaros or Aiolos toCRL4^(CRBN) resulting in the increased ubiquitylation andproteasomal-dependent degradation of these transcription factors in bothMM and T cells. In myeloma cells, targeted knockdown of Ikaros andAiolos mimics the decrease of the myeloma survival factor, IRF4, as wellas the decrease in cell viability observed with IMiD® treatment. In Tcells, Ikaros and Aiolos are known repressors of interleukin-2 (IL-2)transcription, and knockdown of either protein produces an increase inIL-2 similar to IMiD® drug treatment (Gandhi et al., Br J Haematol.; Luet al., Science; Kronke, et al., Science, 2014. 343(6168):301-5.). Thesefindings demonstrated that IMiD® binding confers new functionality tothe CRL4^(CRBN) complexes, raising the possibility that an IMiD®conferred neo-morphic structure is involved.

One further feature of historical and developmental importance in thepharmacology of lenalidomide and related drugs is the speciesspecificity which these compounds exhibit. For example, it has beenshown that mice and rats are insensitive to the teratogenic effects ofthalidomide and lenalidomide (Newman et al., Reprod Toxicol, 1993.7(4):359-90), while primates, including humans, are sensitive.Consistent with the species differences in pharmacology, we demonstratethat mouse splenocytes are resistant to the IL-2 inducing effects ofpomalidomide and that in a mouse A20 cell line engineered to expresshuman cereblon and human Aiolos, mouse Aiolos is not degraded in thepresence of lenalidomide while human Aiolos is

6.9.1. Summary

The Cul4:Rbx1:DDB1:Cereblon E3 ubiquitin ligase complex has beenidentified as the molecular target of a therapeutically important classof molecules known as IMiD® drugs or Immunomodulatory Drugs. IMiD® drugsdirectly bind Cereblon (CRBN) and in the process modulate the activityof the E3 ubiquitin ligase and the resulting stability of its clientproteins. The recently described lenalidomide-mediated recruitment ofthe transcription factors Ikaros (IKZF1) and Aiolos (IKZF3) to the E3complex promoting enhanced ubiquitination and degradation providesinsight into the molecular basis for therapeutic activity of IMiD® drugsin multiple myeloma and other B cell malignancies.

Herein we describe the crystal structure of human CRBN bound to DDB1 andthe IMiD® drug lenalidomide. CRBN binds DDB1 in the same cleft utilizedby other DDB1 and Cullin Associated Factors (DCAFs); however, theinteractions are non-canonical and involve more extensive interactionswith both the beta-propeller A and C domains. The IMiD® binding site iscomprised of a tryptophan ringed hydrophobic pocket which binds theglutarimid moiety common to lenalidomide, thalidomide, and pomalidomide.This binding conformation orients lenalidomide's isoindolinone ringtowards solvent with the functional consequence of altering thesubstrate recognition properties of the E3 ligase.

Using structure guided point mutations and lentiviral knock-in myelomamodels, we show that key IMiD® drug binding site residues are criticalfor drug-mediated myeloma cell antiproliferative effects. Importantly, aspecies specific CRBN polymorphism in rodents proximal to thelenalidomide binding site provides explanation for the long appreciatedspecies specific responsiveness in humans and primates compared withrodents.

6.9.2. Materials and Methods

6.9.2.1 Structural Determination

Cereblon IMiD®-binding domain was purified as follows: The gene encodingthe thalidomide binding domain (TBD) of human CRBN (amino acids 319-427(SEQ ID NO: 5)) or mouse CRBN (amino acids 322-430 (SEQ ID NO: 6)) wascodon optimized and inserted into a pGEX6P-3 vector for expression as aGST-fusion protein in E. coli. BL21 (DE3) Star cells transformed witheither plasmid were grown to OD 0.6 in TB media supplemented with 50 μMzinc acetate, and induced with 0.5 mM IPTG for 4 hours at 37 C. Cellswere resuspended in lysis buffer containing 50 mM Tris pH 7, 150 mMNaCl, 10% glycerol, 2 mM TECP, 1 mM DTT, 100 U/mL benzonase (Novagen),1× Protease Inhibitor Cocktail-EDTA free (SD Biosciences), 0.5 mg/mLlysozyme (Sigma), and sonicated for 30 s before ultracentrifuation for30 min at 100,000×g. GST-fused CRBN was then bound to glutathioneaffinity resin, washed in 50 mM Tris pH 7, 150 mM NaCl, 10% glycerol, 2mM TCEP, 1 mM DTT, and eluted in the same buffer with the addition of 40mM reduced glutathione. The GST tag was removed by overnight cleavage at4 C with PreScission Protease (1 U/mg protein, GE Healthcare). CRBN TBDwas further purified with ion-exchange chromatography by diluting thecleaved protein to 75 mM NaCl using 50 mM Tris pH 7, 2 mM TCEP and 1 mMDTT, and binding to either a Mono S column (mouse TBD) or heparin column(human TBD). Protein was eluted using a gradient from 90 mM to 1M NaCland pooled for size exclusion chromatography. Mouse CRBN TBD waspurified by size exclusion over an S75 16/600 in 5 mM sodium acetate pH6, 10 mM TECP, and 5 mM DTT. Human CRBN TBD was purified over an S7516/600 in 20 mM MES pH 6, 200 mM NaCl, 10 mM TCEP and 1 mM DTT. Eitherthe human or the mouse protein was concentrated to 17 mg/mL.Alternatively, residues of murine 321-429 fused to GST were expressed inE. coli. Cells were lysed by sonication and the soluble fractionpurified using GST-trap, ion exchange and size-exclusion chromatography.Protein was concentration to 28 mg/ml in 50 mM acetate buffer, pH 6.0, 1mM DTT, 10 mM TCEP. Crystals were obtained by sitting drop vapordiffusion by mixing the protein buffer 1:1 with and equilibratingagainst a mother liquor of crystallization buffer. For the mouse unboundTBD, the crystallization buffer contained 100 mM Sodium acetate pH 5,600-800 mM Ammonium sulfate. Crystals were grown at 4 degreescentrigrade and cryoprotected by addition of 20% glycerol and frozenunder liquid nitrogen. Human TBD crystallized in both 100 mM sodiumcacodylate pH 6.5, 200 mM ammonium sulfate, and 30% PEG 8,000, and 100mM sodium cacodylate pH 6.5, 200 mM lithium sulfate, 25% PEG 2000 MME at4 degrees centrigrade. Crystals were cryoprotected by the addition of20% ethylene glycol prior to freezing. Crystals of murine TBD in complexwith CC-220 were formed by sitting drop vapor diffusion. CC-220 wasadded to the protein to a final concentration of 1 mM, and the proteindroplet was mixed 1:1 with, and subsequently equilibrated against areservoir solution of 100 mM MES pH 6.5, 10 mM zinc sulfateheptahydrate, 25% PEG MME 550 and incubated at 4 degrees centrigrade.Crystals were cryoprotected by addition of 20% glycerol and frozen underliquid nitrogen.

The structure of murine cereblon thal-binding domain was solved bysingle wavelength anomalous dispersion using intrinsically bound zincions. Briefly, 480 degrees of data were collected from a single crystalat 1.0 A wavelength. Data were integrated and scaled using HKL2000(Otwinowski et al., Methods in Enzymology, 1997. 276:307-326). Phasingand automated model building were performed with Crank in CCP4i, usingthe following subprograms: AFRO/CRUNCH2/BP3/SOLOMON/Buccaneer (Abrahamset al., Acta Crystallogr D Biol Crystallogr, 1996. 52(Pt 1):30-42; deGraaff, R. A., et al., Acta Crystallogr D Biol Crystallogr, 2001. 57(Pt12):1857-62; Pannu et al., Acta Crystallogr D Biol Crystallogr, 2004.60(Pt 1): 22-7; Pannu et al., Acta Crystallogr D Biol Crystallogr, 2011.67(Pt 4):331-7). Subsequent manual model building and refinement wereperformed using Coot and Refmac5, respectively (Murshudov et al., ActaCrystallogr D Biol Crystallogr, 2011. 67(Pt 4):355-67; Emsley et al.,Acta Crystallogr D Biol Crystallogr, 2010. 66(Pt 4):486-501). Subsequentstructures were solved by molecular replacement using Phaser (McCoy etal., J Appl Crystallogr, 2007. 40(Pt 4): 658-674).

Human CRBN (amino acids 40-442) (SEQ ID NO: 8) fused to a N-terminalZZ-6×His tag with a thrombin cleavage site and full length human DDB1with or without a C-terminal strep-tag were co-expressed in SF9 insectcells using ESF921 medium supplemented with 50 μM zinc acetate. Cellswere resuspended in 8 volumes Lysis Buffer (50 mM Tris pH 7.5, 500 mMNaCl, 10% Glycerol, 10 mM Imidazole, 1 mM TCEP) plus 1× proteaseinhibitor cocktail and 2,000 Units TurboNuclease for 1 hour at 4° C. Thelysate was centrifuged at 105,000×g for 1 hour and the supernatant wasloaded to 5 mL Ni-NTA, pre-equilibrated in lysis buffer. CRBN-DDB1 waseluted using a stepwise method with Elution Buffer (50 mM Tris pH 7.5,500 mM NaCl, 10% Glycerol, 500 mM Imidazole, 1 mM TCEP). Peak fractionswere pooled and the ZZ-6×His tag was cleaved by incubation with thombinovernight at 4 C (1 mg thrombin/100 mg target protein, Enzyme Research).Protein was subsequently diluted to 200 mM NaCl. Diluted complex wasimmediately applied to a HiTrap™ ANX 5 mL column (GE Lifesciences).Sample was loaded under a Tris pH 7.5 environment and changed on-columnto Bis-Tris pH 6.0. Protein was eluted using a linear gradient from 200mM to 1M NaCl. CRBN-DDB1 complex protein was polish purified by S-400gel filtration (GE Lifesciences). Complexed protein, as identified bySDS-PAGE, was pooled and setup in crystallization or stored at −80° C.in protein buffer (10 mM MES pH 6.0, 200 mM NaCl, 5 mM TCEP). CRBN-DDB1at 30.2 mg/ml in storage buffer consisting of 10 mM MES pH6.0, 200 mMNaCl, 5 mM TCEP, or in an alternative buffer of 10 mM HEPES pH 7, 250 mMNaCl, 3 mM TCEP. CRBN-DDB1 was crystallized by sitting drop vapordiffusion. 1 mM lenalidomide was added to the mixture ofCRBN-DDB1-Lenalidomide mixed 1:1 with, and subsequently equilibratedagainst, a reservoir solution containing 18% (w/v) PEG 10K (HamptonResearch, Aliso Viejo, Calif.) and 100 mM HEPES pH 7.5 (HamptonResearch, Aliso Viejo, Calif.). Initial crystallization conditions wereidentified by sparse matrix screening. Co-crystals appeared in sevendays and reached dimensions of 0.10 mm×0.025 mm×0.025 mm by 21 days.Before data collection, crystals were cryoprotected in the reservoirsolution supplemented with 20% Ethylene glycol and frozen in liquidnitrogen. The structure of human cereblon:DDB1 was solved by molecularreplacement using Phaser (McCoy et al., J Appl Crystallogr, 2007. 40(Pt4): 658-674), with DDB1 (PDB code 3EOC) and the murine cereblon TBD assearch models. Subsequent manual model building and refinement wereperformed using Coot and Refmac5, respectively (Murshudov et al., ActaCrystallogr D Biol Crystallogr, 2011. 67(Pt 4):355-67; Emsley et al.,Acta Crystallogr D Biol Crystallogr, 2010. 66(Pt 4):486-501) For thehuman CRBN-DDB1-CC-220 structure, CC-220 was added to the protein at 1mM and was mixed 1:1 with buffer containing 200 mM sodium fluoride and20% PEG 3350 and equilibrated against a mother liquor containing thesame buffer at 20 C. Crystals were cryoprotected by the addition of 20%ethylene glycol.

6.9.2.2 Cell Lines

The DF15R cell line, previously shown to lack detectable CRBN protein,was grown and cultured as previously described (Lopez-Girona et al.,Leukemia, 2012. 26(11):2326-35).

6.9.2.3 Wild-Type and Mutant CRBN Plasmids

Lentiviral expression vectors were produced in-house. Lentiviralparticles were generated using HEK-293T cells and infection was doneutilizing spinoculation methodology. Selection was performed 1 weekafter initial infection. DF15 and DF15R cells were transduce and a poolof puromycin-resistant cells selected and screened by Western blottinganalysis with anti-CRBN antibody (Lopez-Girona et al., Leukemia, 2012.26(11):2326-35). We confirmed the presence of the corresponding CRBNmutant versions by DNA genomic sequencing in all cell lines.

6.9.2.4 CRBN Short Hairpin RNA (shRNA) Constructs

Inducible shRNA constructs targeting CRBN or a control construct (OpenBiosystems) were transduced using spinoculation methodology into themultiple myeloma cell lines H929 and U266. Stably transduced cells wereselected with puromycin. Inducible shRNA expression (marked by RFP) wasmonitored by fluorescence microscopy and flow cytometry using 1 μg/mLdoxycycline. CRBN protein expression was quantified by Western blotting.Cell proliferation and viability were assessed by 7AAD/flow cytometryassays. 6.9.2.5 Immunoblot and Immunohistochemistry

Western blotting was performed with antibodies to Aiolos (Santa Cruz)IRF4, c-Myc, p21, p27, and ppRb (Ser608). CRBN65 antibody was used forCRBN protein detection (Lopez-Girona et al., Leukemia, 2012.26(11):2326-35). Cereblon immunohistochemistry (IHC) was performed onthe Bond-Max® automated slide stainer (Leica Microsystems, BuffaloGrove, Ill.) using the Bond Polymer Refine® Detection system. Formalinfixed paraffin embedded (FFPE) cell pellets were sectioned at fourmicron thick and deparaffinized on the Bond-Max instrument. Antigenretrieval was performed with Epitope Retrieval® 2 (ER2, pH 9.0) for 20min at 100° C. The slides were blocked for endogenous peroxidaseactivity with Peroxide Block for 5 minutes at room temperature. Sectionswere then incubated with the rabbit monoclonal antibody CRBN65 at a1:4,000 dilution for 15 min at room temperature. Post-Primary andhorseradish peroxidase (HRP) labeled Polymer were incubated at theinstrument's default conditions. Antigen-antibody complex was thenvisualized with hydrogen peroxide substrate and diaminobenzidinetetrahydrochloride (DAB) chromogen. Slides were counterstained withhematoxylin.

6.9.2.6 Thalidomide Analog Bead Assay to Measure Compound Binding toEndogenous CRBN

Coupling of thalidomide analog to FG-magnetic nanoparticle beads(Tamagawa Seiko Co. Tokyo, Japan) was carried out as described (Ito etal., Science, 2010. 327(5971):1345-50), and cell extract binding assaysto these beads were performed with minor modifications. DF15, DF15R orDF15R derived cell line extracts were prepared in NP 40 lysis buffer(0.5% NP40, 50 mM Tris HCl (pH 8.0), 150 mM NaCl, 0.5 mM DTT, 0.25 mMPMSF, 1× protease inhibitor mix (Roche, Indianapolis, Ind.) atapproximately 2×108 cells per ml (20 mg protein/ml). Cell debris andnucleic acids were cleared by centrifugation (14,000 rpm 30 min 4° C.).In competition experiments 0.5 ml (3-5 mg protein) aliquots of theresulting extracts were preincubated (15 min room temp.) with 5 μl DMSO(control) or 5 μl compound at varying concentrations in DMSO.Thalidomide analog-coupled beads (0.3-0.5 mg) were added to proteinextracts and samples rotated (2 hours, 4° C.). Beads were washed threetimes with 0.5 ml NP40 buffer, and then bound proteins were eluted withSDS-PAGE sample buffer. Samples were subjected to SDS-PAGE andimmunoblot analysis, performed using anti-CRBN 65-76 (Lopez-Girona etal., Leukemia, 2012. 26(11):2326-35) (1:10,000 dilution) for allstudies; other antisera dilutions were DDB1 (1:2,000 dilution) orβ-actin (1:10,000 dilution). In thalidomide affinity bead competitionassays, a LI-COR Odessey™ system was used to quantify CRBN band densityand relative amounts of CRBN were determined by averaging at least threeDMSO controls and expressing CRBN in each competition sample as percentinhibition of CRBN protein relative to the averaged controls as 100%binding.

6.9.3. Results

6.9.3.1 Crystal Structure of CRBN in Complex with DDB1 and Lenalidomide

The structure of CRBN reveals that CRBN is a DCAF that does not exhibita WD-repeat architecture typical of the class. The CRBN structure (FIG.12) reveals two distinct domains: an N-terminal Lon-like domain (LLD),and a C-terminal TBD. The structure reveals that the DDB1 and IMiD®binding sites occur on opposite sides of the cereblon surface. A humanpolymorphism linked to mental retardation has been found in CRBNresulting in premature truncation of CRBN at amino acid 419. The deletedregion occurs within the IMiD® binding domain, with a short helicalregion and a β-strand removed (deleted region shown in red in FIG. 12).The deleted region occurs at the interface between the LLD and TBD, andtruncation of these residues might be expected to deleteriously affectthe domain structure and stability of CRBN.

The CRBN Lon-like domain (LLD) spans residues 76-318 (SEQ ID NO: 9) andcontains the DDB1 binding motif. Structural alignment with Bacillussubtilis Lon N-terminal domain yields an RMSD of 2.4 Angstroms over 165aligned residues (FIG. 13) (Duman et al., J Mol Biol, 2010. 401(4): p.653-70). However, as shown in FIG. 13, the DDB1 binding motif and theIMiD® binding site do not exhibit any homology with the examined Londomains. When compared to B. subtilis Lon, the DDB1 binding motifappears to have been inserted into the Lon-like domain, and is composedof a series of helices between CRBN residues 188 and 248 (SEQ ID NO:10). CRBN binds between the beta propeller A (BPA) and the betapropeller C (BPC) domains of DDB1 in a similar location to other DCAFs(e.g. DDB2 or DCAF9), as well as to the viral DDB1 binding proteins Hbxand SV5V (Li et al., Nat Struct Mol Biol, 2010. 17(1): p. 105-11).However, although CRBN binds to DDB1 in the same region, the nature ofthe interaction with DDB1 exhibits differences compared to DDB2, SV5V orHbx. Previously studied DCAFs position a helix-turn-helix motif in theDDB1 binding site which predominantly forms interactions with the BPCdomain (FIG. 14, helices c and d) (Li et al., Nat Struct Mol Biol, 2010.17(1): p. 105-11). CRBN interacts with DDB1 via a series of helices;however, these do not superpose with the DCAFs which have beenstructurally characterized (FIG. 14). In CRBN, residues 221-248 (SEQ IDNO: 11) form helices which interact with the DDB1 BPC domain (helix aand b, FIG. 14). CRBN residues 191-197 (SEQ ID NO: 12) also interactwith DDB1 BPC in a proximal region to DDB2 (FIG. 13). However, as wellas interacting with the BPC domain, CRBN also positions a helix composedof residues 198 to 209 (SEQ ID NO: 13) to interact with the BPA domainof DDB1, the first example of such an interaction (helix e, FIG. 14).After the DDB1 binding motif, structural homology with the Lon domain isrestored between residue 249 and 318 (SEQ ID NO: 14) which form a4-helix bundle, thus leading to the IMiD® binding domain, or thalidomidebinding domain (TBD) at residues 319-428 (SEQ ID NO: 15).

The TBD is located on the face of CRBN which is oriented away from theDDB1-binding site. The TBD is composed of a six-stranded antiparallelβ-sheet core, with a structural zinc ion, coordinated by four cysteineresidues, located ˜18 Å from the IMiD® binding site (FIG. 18). The IMiD®binding pocket itself is formed by three tryptophan residues, Trp380,Trp386, and Trp400, with a phenylalanine residue at the base (Phe402)(FIG. 18). These residues form a small hydrophobic pocket (tri-Trppocket) in which the glutarimide portion of lenalidomide isaccommodated. Within the tri-Trp pocket there are two hydrogen bondsbetween the glutarimide ring and the protein backbone at residues His378and Trp380 (FIG. 13), and a further hydrogen bond with the sidechain ofHis378. The isoindolinone ring of lenalidomide is not enclosed withinthe hydrophobic pocket, and instead presents on the surface of theprotein interacting with a beta-turn encompassing residues 351-353(indicated by the symbol β in FIG. 13). The carbonyl oxygen of theisoindolinone ring is oriented towards the sidechain of His357; however,the distance is slightly too long for a hydrogen bond to form (4.1 Å).Similarly, the aniline amino group of lenalidomide is oriented towardsGlu377, but at a distance too great for an interaction to be made (5.5Å).

In determining whether CMA drug interaction with CRBN may serve to alterthe specificity of the Cul4 ubiquitin ligase complex by recruitment ofnew partners or altering the substrate affinity of its clientsubstrates, it is intriguing that the isoindolinone ring is exposed onthe surface of the CRBN-IMiD® complex, indicating that this part of theIMiD® molecule would be available to form part of a ‘neomorphic’interface in substrate recruitment. In this instance, the unusedhydrophobic and polar bonding potential of the IMiD® and the adjacentprotein surface could play a key role in altering/enhancing bindingpartner recruitment.

The TBD can be expressed and purified in isolation, and we have usedthis system to obtain crystal structures of the murine CRBN TBD incomplex with thalidomide and pomalidomide. The TBD structure wasinitially solved by taking advantage of the predicted zinc binding sitein a single wavelength anomalous dispersion experiment at a normalsynchrotron wavelength of 1.0 Å. We noted that the electron densityfavors the S-enantiomer of thalidomide, which was crystallized as aracemic mixture. We subsequently confirmed that S-thalidomide binds CRBNmore tightly than the R-enantiomer by competition for thalidomideimmobilized beads (FIG. 21A-21C) consistent with previous results usingthe conformationally stable R- and S-methyl-pomalidomide analogs(Lopez-Girona et al., Leukemia. 26(11):2326-35). The core features ofthe IMiD® binding site which interact with the glutarimide ring are wellconserved between the lenalidomide, thalidomide and pomalidomidestructures, with the three tryptophans providing the key interactions tothe glutarimide ring. The two hydrogen bonds to His378 and Trp380 arealso conserved; however, the third hydrogen bond to the sidechain ofHis378 is not made. There is a striking difference between thelenalidomide structure and the others: the two beta-strands composed ofresidues 346-363 (SEQ ID NO: 16) are absent in both the thalidomide andthe pomalidomide structures (FIGS. 15, 16 and 17). There are fourprotein-drug pairs in the asymmetric unit for both the thalidomide andpomalidomide structures. In all proteins in the asymmetric unit in thepomalidomide structure the beta-strand region is completely disordered(FIG. 17). The same is true for one protein (chain A) in the thalidomidestructure (FIG. 16); however, in chains B and D the beta-strands haveadopted an alternative conformation where these residues bind thephthalimide ring of thalidomide from an adjacent molecule in theasymmetric unit (FIG. 20). This reciprocal arrangement forms a dimer inthe crystal lattice, with Tyr355 stacking against the accessible surfaceof the IMiD®. There is no evidence of dimerization in the presence orabsence of IMiD® (data not shown). The change in conformation provides asubstantial change in the surface of CRBN in the IMiD® binding sitevicinity, with the intriguing potential to influence binding partnerrecruitment. The extent to which different conformations are influencedby protein truncation or the lattice environment is unknown.

The alternative substitutions on the isoindolinone/phthalimide ringprovide a second potential mechanism by which to selectively recruitbinding partners to the Cul4:DDB1:CRBN E3 ligase complex. Lenalidomideand pomalidomide differ from thalidomide in possessing an NH₂substitution on the isoindolinone/phthalimide ring. In the lenalidomidestructure this NH₂ moiety is oriented towards Glu377, where in thepomalidomide structure this group appears to be able to orient intoeither direction as the electron density supports differing orientationsin the different chains in the asymmetric unit (data not shown).

We further sought to confirm that the IMiD binding pocket is present inthe absence of ligand by determining the structure of apo TBD. Thisstructure clearly shows that the pocket can exist in a similarconformation in the absence of ligand (Table 2)

TABLE 2 Crystallographic Statistics Protein: CRBN:DDB1: CRBN(TBD):CRBN(TBD): Ligand Lenalidomide Pomalidomide Thalidomide Data collectionCLS ALS 8.2.1 APS site CMCF-08ID SER-CAT 22ID Wavelength ({acute over(Å)}) 1.0 1.0 1.0 Resolution 50-3.0 50-2.0 50-1.88 Range ({acute over(Å)}) (3.12-3.01)* (2.11-2.00) (1.95-1.88) Spacegroup P2₁2₁2₁ I23 I23Cell dimensions 71.8 129.1 198.7 143.3 143.3 143.3 143.1 143.1 143.1({acute over (Å)}) Angles (deg) 90 90 90 90 90 90 90 90 90 No. of 22844483521 1750276 observations No. of unique 37313 25718 76864 observationsCompleteness 98.5 (85.8)* 92.3 (92.4) 99.9 (100.0) (%) I/σI 10.1 (2.6) 10.1 (5.4)  38.4 (6.6)  R_(merge (%)) 18.1 (72.3)   9.0 (24.5) 8.9(59.9) Refinement statistics R_(work)/R_(free) 20.3/27.8 19.7/24.018.0/22.9 RMSD for bond 0.012 0.017 0.014 length ({acute over (Å)}) RMSDfor bond 1.25 1.723 1.676 angles (deg) *Figures in parentheses are forthe outer resolution shell.

Table 3 below sets forth the atomic coordinates forCRBN:DDB1:Lenalidomide.

Table 4 below sets forth the atomic coordinates for CRBN(TBD):Pomalidomide.

Table 5 below sets forth the atomic coordinates for CRBN (TBD):Thalidomide.

Table 6 below sets forth the atomic coordinates for CRBN: DDB1: CC-220.

Table 7 below sets forth the atomic coordinates for CRBN (TBD): CC-220.

Table 8 below sets forth the atomic coordinates for unbound CRBN-CRBN(TBD) (Apo).

Lengthy table referenced here US20190030019A1-20190131-T00001 Pleaserefer to the end of the specification for access instructions.

A search for structural homologs to the TBD reveals that despite verylow sequence identity (<14%), the same fold is found in other proteinsincluding methionine sulfoxide reductase (MSR), an enzyme involved inthe repair of oxidized proteins, dsRNA binding proteins RIG-I, MDA5 andLGP2 which are involved in sensing viral RNAs as part of the innateimmune response (Lu et al. Structure, 2010. 18(8):1032-43; Li et al. JBiol Chem, 2009. 284(20): 13881-91). Despite sharing the same fold, thetri-Trp pocket residues are not conserved in any of these structurallysimilar proteins, indicating that these cannot bind IMiD® drugs in thesame manner as CRBN. However, CRBN orthologues can be identified acrossanimal and plant kingdoms, and these proteins exhibit 100% sequenceconservation in the IMiD® drug binding pocket (FIG. 19). This level ofsequence conservation is indicative of strong functional constraint(s),which suggests there may be an endogenous ligand with which IMiD® drugscompete. Tryptophan residues 380 (W380), 386 (W386) and 400 (W400) arefully conserved across CRBN orthologues (FIG. 19). The glutarimidebinding pocket formed by these three tryptophan residues is reminiscentof the aromatic pockets used for binding methylated lysine and/orarginine found in royal family proteins containing chromodomains, tudordomains, plant homeo domain (PHD) fingers and malignant brain tumor(MBT) repeats, as well as bromodomains for binding to acetylated lysinesand the tryptophan box of betaine-binding proteins such as ProX31 andBetP32. However, our isothermal titration calorimetry (ITC) analysisshowed no significant binding affinity to modified lysines, arginines orbetaines (data not shown).

A combination of mutations at both Tyrosine 384 (Y384) and W386 has beenreported to cause a loss of the IMiD® drug effects. As shown in FIG. 15,W386 is part of the lenalidomide binding site and mutation of thatresidue would be expected to have consequences for IMiD® drug binding.Y384 however does not make any direct interactions with lenalidomide,and might be expected to have a more general effect on the stability ofthe domain.

6.9.3.2 Mutational Analysis of Residues Proximal to the IMiD® BindingSite

To better understand the role of the residues involved in the CRBN-IMiDinteractions in a cellular context, we performed mutagenesis of residuesW386 or W400 to alanine and used lentiviral expression vectors tore-express full length wild type (CRBN^(WT)), W386A (CRBN^(W386A)) orW400A (CRBN^(W400A)) mutant versions of CRBN in a CRBN deficient myelomacell line (DF15R) (Lopez-Girona et al., Leukemia. 26(11):2326-35).Transduction of the lentiviral constructs into DF15R cells and selectionwith puromycin generated cell lines that stably expressed wild type ormutant forms of CRBN at levels similar to the matched IMiD®-sensitiveDF15 cell line (Lopez-Girona et al., Leukemia. 26(11):2326-35) (FIGS.24A-24B). Immunoprecipitation-Western blotting analysis confirmed thatsimilar to recombinant, wild type CRBN, mutants CRBN^(W386A) andCRBN^(W400A) interacted with DDB1 indicating that these proteins wereproperly folded and competent to form CRL4^(CRBN) complexes in cells(FIG. 24C (Ito et al., Science, 2010. 327(5971):1345-50). Cell extractsfrom these lines were then used to assay the ability of CRBN to bindIMiD® compound. We used the thalidomide analog-coupled affinity beadassay (Ito et al., Science, 2010. 327(5971): 1345-50; Lopez-Girona etal., Leukemia. 26(11):2326-35) (FIG. 24D) to demonstrate binding ofrecombinant CRBN to IMiD® compounds in cell extracts. Similar to theendogenous protein in DF15 cell extracts, the recombinant CRBN^(WT)expressed in DF15R was able to bind thalidomide analog-beads (FIG. 22A),and preincubation of cell extracts with free thalidomide or pomalidomidecompeted for binding to the beads. In contrast, the tryptophan mutantsCRBN^(W386A) and CRBN^(W400A) were unable to bind thalidomideanalog-beads (FIG. 22A), consistent with the structural information thatboth tryptophan residues in CRBN are needed for the interaction withIMiD® compounds.

The antiproliferative effect of IMiD® compounds on myeloma cells ismediated through CRBN protein. Thus, engineered cells (FIGS. 25A-25F)(Lopez-Girona et al., Leukemia. 26(11):2326-35; Zhu et al., Blood. 2011.118(18):4771-9) or cells made resistant to IMiD® drugs (Lopez-Girona etal., Leukemia. 26(11):2326-35) that lack detectable levels of CRBN,e.g., DF15R, become insensitive to the antiproliferative effects of theIMiD® compounds (FIG. 22B; FIGS. 25A-25F). Significantly, there-expression of a single recombinant protein, CRBN^(WT), is sufficientto restore the sensitivity to IMiD® compounds in the resistant lineDF15R (FIG. 22B) as well as in other cell lines (data not shown). Inthese cells, re-expression of CRBN^(WT) also restores IMiD®-induceddegradation of aiolos, and, as expected, restores the inhibition ofc-Myc, IRF4, and phophorylated pRB expression (FIG. 22C). All of thesedownstream effects are consistent with the regained antiproliferativeeffect of pomalidomide (Gandhi et al., Br J Haematol.; Lu et al.,Science; Kronke, et al., Science, 2014. 343(6168):301-5; Lopez-Girona etal. Br J Haematol, 2011. 154(3):325-36). In contrast, expression of theIMiD®-binding defective mutants, CRBN^(W386A) or CRBN^(W400)A, does notre-sensitize DF15R cells to the antiproliferative effects of IMiD® drugs(FIGS. 22B and 22C). These cellular data are consistent with thestructural data indicating that both W386 and W400 residues mediate CRBNbinding to IMiDs®, and CRBN mediates the antiproliferative effectscharacteristic of IMiD® compounds in myeloma cells.

6.9.3.3 Mutation of Variable Residues in the IMiD® Binding Site of CRBN

Since we hypothesized that IMiDs® are essential for altering theinteraction between CRBN and substrate, we also investigated the role ofother proximal residues. It is known that rodents do not respond toIMiD® drugs in the same way that humans do. Rodents appear to beresistant to the IL-2 induction (FIGS. 26A-26B), antiproliferativeeffects and also IMiD® compound induced teratogenicity (Newman et al.,Reprod Toxicol, 1993. 7(4):359-90). A key step in understanding IMiD®biology and ultimately engineering IMiD® analogs without teratogenicitymay indeed come from pin-pointing the key features which underlie thebiological differences seen between rodents and humans. Within the IMiD®binding domain there are four differences between mouse and humanproteins. Two of the variable residues are proximal to the IMiD® bindingsite (FIG. 19). One of these residues features a substantial change inproperties from an acidic residue (glutamate 377) in human to ahydrophobic residue (valine) in mouse and rat.

To probe the function of the residues proximal to the bound IMiD® drug,we performed mutagenesis of residue E377 to valine in the human CRBNsequence and re-expressed the protein using a lentiviral system in DF15Rcells. Cell extracts from this line were used to assay the ability ofCRBN^(E377V) to bind IMiD® compound. Similar to the recombinantCRBN^(WT), but in contrast to the CRBN^(W386A) or CRBN^(W400A) mutants,the CRBN^(E377V) mutant was able to bind thalidomide analog-beads, andthis binding was competed by preincubation of cell extracts with freethalidomide or pomalidomide comparable to CRBN^(WT) (FIG. 23A). This isconsistent with the structure that shows E377V is proximal to but doesnot directly interact with bound lenalidomide. CRBN^(E377)Vre-expression in DF15R was unable to rescue sensitivity to pomalidomideor to rescue the degradation of Aiolos (FIG. 23B and FIG. 23B insert).IMiD® binding to CRBN has been shown to enhance both the recruitment toCRL4CRBN and the degradation of Ikaros and Aiolos Gandhi et al., Br JHaematol.; Lu et al., Science; Kronke, et al., Science, 2014.343(6168):301-5). To determine whether Aiolos binding had been altered,we performed pull-down assays to compare the ability of CRBN^(WT) orCRBN^(E377V) to interact with Aiolos in the presence or absence of IMiD®compounds.

The function of the residues proximal to the bound IMiD® drug indegradation of CRBN substrates induced by IMiD® drug was studied. 293FTCRBN−/− cells were transiently transfected with plasmids expressingV5-tagged IKZF1, FLAG-tagged IKZF3, Myc-tagged Substrate X, GFP, humanCRNB (hCRBN) or variants thereof, or mouse CRBN (mCRBN) or variantsthereof. Thirty-six hours after transfection, cells were treated withDMSO, 10 μM lenalidomide or 1 M CC-885 for additional 12 hours. Cellswere then wished with ice-cold 1×PBS twice, lysed in buffer A [50 mMTris. CL, 150 mM NaCL, 1% triton-x 100, complete protease inhibitortablet (roche), phosphatase inhibitor tablet (roche)]. Whole cellextracts were then harvested and subjected to immunoblot analysis. Theresults are shown in FIG. 27. As shown, V388 is essential for thedestruction of Ikaros (IKZF1) or Aiolos (IKZF3) by lenalidomide. Thisresult indicates that residue 388 of CRBN plays an important role indegradation of CRBN substrates, e.g., Ikaros or Aiolos, induced by IMiD®drug.

6.9.4. Discussion

Ito et al. first reported CRBN as the primary molecular target ofthalidomide, and through mutagenesis demonstrated that the C-terminaldomain encompassed the thalidomide binding domain (Ito et al., Science,2010. 327(5971):1345-50).

Herein, we have presented the crystal structure of CRBN in complex withDDB1 and lenalidomide, thus providing the first structural descriptionof IMiD® drug binding. The IMiD®-binding site is a shallow hydrophobicpocket on the surface of CRBN: three tryptophan residues form thebinding site for the glutarimide ring of the IMiD® drug, with 3 hydrogenbonds observed between CRBN and the glutarimide ring. The glutarimidering is a defining feature of the IMiD® class of molecules and allIMiD®-CRBN structures solved to date replicate the CRBN-IMiD bindinginteraction described herein.

We have demonstrated that IMiD® binding and cellular function isdependent upon these key tryptophan interactions by comparing mutantknock-ins to wild type CRBN in a CRBN-deficient myeloma cell line,DF15R. We further used the knock-in system to study a glutamate residue,E377, which although proximal to bound lenalidomide, does not directlyinteract with the ligand. E377 is of keen interest as this residue is avaline in rodent species, which are resistant to teratogenic and othercellular IMiD® drug effects. We observe that knock-in of a human E377Vmutant CRBN behaves in an identical manner to the knock-in of murineCRBN into our human myeloma cell line: neither mouse CRBN, nor humanE377V mutant CRBN are able to rescue the IMiD® response although IMiD®binding is clearly evident (FIGS. 23A-23B). In addition, we found thatresidue 388 of CRBN is essential for the destruction of Aiolos andIkaros by lenalidomide. Of note is that we have not detected an E377Vmutation in the setting of clinical resistance but our work here impliesthat a single amino acid change could mediate resistance to IMiD® drugs.CRBN down-regulation is certainly a mode of IMiD® resistance asevidenced by our in vitro experiments and has been suggested by a numberof reports as a mechanism for innate or acquired resistance to IMiD®drugs in the clinical setting.

We establish that IMiD® drug binding alone, although necessary forinducing the E3 ligase mediated degradation of Aiolos and Ikaros, maynot be sufficient as demonstrated here with the E377V mutant.Interestingly, the lenalidomide isoindolinone group is presented on thesurface of the CRBN protein. This binding mode generates a surface witha number of available hydrogen bonds from both the protein andlenalidomide in the proximity of an exposed hydrophobic group. IMiD®drug binding to CRBN has been demonstrated to increase the recruitmentof substrates (e.g., Ikaros and Aiolos) to the ubiquitin ligase complexand enhance their degradation Gandhi et al., Br J Haematol.; Lu et al.,Science; Kronke, et al., Science, 2014. 343(6168):301-5.). It is aninteresting finding by us that V388 of CRBN is essential for IMiD® drug(e.g., lenalidomide) induced degradation of Ikaros and Aiolos. Theunsatisfied bonding potential around the bound IMiD® drug couldtherefore form the basis of an artificially introduced interactionhotspot, thereby conferring a pharmacologically induced ‘neomorphic’function to this E3 ligase.

However, in the case of CRBN, we have shown that the IMiD® bindingpocket is extremely conserved across the known orthologues, whichindicates that IMiD® drugs may be binding in place of an endogenousligand, which has yet to be identified. There are several examples ofendogenous ligands that have been demonstrated to regulate substraterecruitment to ubiquitin ligase complexes in plant systems. For example,auxin and jasmonate are small molecule regulators of ligases in plants(Tan et al. Nature, 2007. 446(7136):640-5; Chini et al., Nature, 2007.448(7154):666-71). Similarly, a number of natural products exhibitpharmacological activity by scaffolding macromolecular interactions(Thiel et al. Angew Chem Int Ed Engl, 2012. 51(9):2012-8).

The ability for a small molecule to scaffold a specific macromolecularinteraction to an E3 ubiquitin ligase has particularly excitingimplications for drug discovery. We have observed several categories ofvariation proximal to the IMiD® drug binding site: variations in thepresentation and substitution pattern of the solvent exposed ligandgroups, protein conformational differences, and species sequencedifferences. To fully rationalize the role of these in IMiD® drugbiology, several further advancements are anticipated, such asidentification of the endogenous ligand(s) and the binding mode of thesubstrate proteins, such as Aiolos, when recruited to theCul4:Rbx1:DDB1:CRBN complex upon IMiD® drug treatment. By describing thecrystal structure of an IMiD® bound to CRBN, a substrate adapter for anE3 ubiquitin ligase, progress towards the rational design of ubiquitinligase modulators is made.

Throughout this application various publications have been referenced.The disclosures of these publications in their entireties are herebyincorporated by reference in this application in order to more fullydescribe the state of the art to which this invention pertains. Althoughthe invention has been described with reference to the examples andembodiments provided above, it should be understood that variousmodifications can be made without departing from the spirit of theinvention.

LENGTHY TABLES The patent application contains a lengthy table section.A copy of the table is available in electronic form from the USPTO website(http://seqdata.uspto.gov/?pageRequest=docDetail&DocID=US20190030019A1).An electronic copy of the table will also be available from the USPTOupon request and payment of the fee set forth in 37 CFR 1.19(b)(3).

1.-73. (canceled)
 74. A method of identifying a test compound thatinduces a cereblon (CRBN) conformational change or an alteration ofproperties of a CRBN surface, wherein the method comprises: (a)contacting the test compound with CRBN, (b) inducing a CRBNconformational change or an alteration of properties of an adjacent CRBNsurface, and (c) assessing the CRBN conformational change or thealteration of properties of the adjacent CRBN surface, wherein the CRBNconformational change or the alteration of properties of the adjacentCRBN surface are indicative of a test compound that induces the CRBNconformational change or the alteration of properties of the CRBNsurface; and wherein the CRBN conformational change or the alteration ofproperties of the CRBN surface occurs in a CMA binding pocket of theCRBN, or within an adjacent region thereof.
 75. The method of claim 74,wherein the test compound has a specific downstream biological activityand wherein the CRBN conformational change or the alteration ofproperties of the adjacent CRBN surface is indicative of the testcompound having the specific downstream biological activity.
 76. Themethod of claim 75, wherein the method further comprises assaying thespecific downstream biological activity.
 77. The method of claim 75,wherein the method further comprises administering the test compound toa patient, wherein the specific downstream biological activity ismodulated in the patient, and wherein optionally the patient has adisease, and one or more symptoms of the disease are alleviatedfollowing administration of the test compound.
 78. The method of claim74, wherein the test compound has a specific therapeutic efficacy andwherein the CRBN conformational change or the alteration of propertiesof the adjacent CRBN surface is indicative of the test compound havingthe specific therapeutic efficacy.
 79. The method of claim 78, whereinthe method further comprises administering the test compound to apatient having a disease, wherein one or more symptoms of the diseaseare alleviated following administration of the test compound.
 80. Themethod of claim 78, wherein the method further comprises administeringthe test compound to a patient having a disease, disorder or condition,wherein one or more symptoms of the disease, disorder or condition arealleviated following administration of the test compound.
 81. The methodof claim 74, wherein the conformational change or alteration has aneffect on W380, W386 and/or W400 of CRBN; has an effect on E377 of CRBN;or has an effect on V388 of CRBN; wherein the CRBN is human CRBN. 82.The method of claim 74, wherein the CRBN conformational change or thealteration of properties of the CRBN surface is assessed by x-raycrystallography.
 83. The method of claim 74, wherein the CRBN is furtherbound to Damaged DNA Binding protein 1 (DDB1), Cullin-4 (Cul4),homeobox-leucine zipper protein ROC1 (Roc1), or any combination thereof.84. The method of claim 74, wherein the CRBN is further bound to DDB1.85. The method of claim 74, wherein the CRBN is human CRBN or murineCRBN.